diff --git a/addons/account_followup/tests/test_account_followup.py b/addons/account_followup/tests/test_account_followup.py
index 14f458de98d..8ddf3f82288 100644
--- a/addons/account_followup/tests/test_account_followup.py
+++ b/addons/account_followup/tests/test_account_followup.py
@@ -44,8 +44,7 @@ class TestAccountFollowup(TransactionCase):
                                                                             'quantity': 5, 
                                                                             'price_unit':200
                                                                                  })]})
-        wf_service = netsvc.LocalService("workflow")
-        wf_service.trg_validate(uid, 'account.invoice', self.invoice_id, 'invoice_open', cr)
+        self.registry('account.invoice').signal_invoice_open(cr, uid, [self.invoice_id])
         
         self.voucher = self.registry("account.voucher")
         
diff --git a/addons/account_payment/account_payment.py b/addons/account_payment/account_payment.py
index d67db60e590..c57c83aa765 100644
--- a/addons/account_payment/account_payment.py
+++ b/addons/account_payment/account_payment.py
@@ -135,9 +135,8 @@ class payment_order(osv.osv):
         return True
 
     def set_done(self, cr, uid, ids, *args):
-        wf_service = netsvc.LocalService("workflow")
         self.write(cr, uid, ids, {'date_done': time.strftime('%Y-%m-%d')})
-        wf_service.trg_validate(uid, 'payment.order', ids[0], 'done', cr)
+        self.signal_done(cr, uid, [ids[0]])
         return True
 
     def copy(self, cr, uid, id, default=None, context=None):
diff --git a/addons/account_voucher/account_voucher.py b/addons/account_voucher/account_voucher.py
index de9cebdd09b..2046d787ef3 100644
--- a/addons/account_voucher/account_voucher.py
+++ b/addons/account_voucher/account_voucher.py
@@ -820,10 +820,7 @@ class account_voucher(osv.osv):
         return vals
 
     def button_proforma_voucher(self, cr, uid, ids, context=None):
-        context = context or {}
-        wf_service = netsvc.LocalService("workflow")
-        for vid in ids:
-            wf_service.trg_validate(uid, 'account.voucher', vid, 'proforma_voucher', cr)
+        self.signal_proforma_voucher(cr, uid, ids)
         return {'type': 'ir.actions.act_window_close'}
 
     def proforma_voucher(self, cr, uid, ids, context=None):
@@ -1506,7 +1503,6 @@ class account_bank_statement(osv.osv):
 
     def create_move_from_st_line(self, cr, uid, st_line_id, company_currency_id, next_number, context=None):
         voucher_obj = self.pool.get('account.voucher')
-        wf_service = netsvc.LocalService("workflow")
         move_line_obj = self.pool.get('account.move.line')
         bank_st_line_obj = self.pool.get('account.bank.statement.line')
         st_line = bank_st_line_obj.browse(cr, uid, st_line_id, context=context)
@@ -1514,7 +1510,7 @@ class account_bank_statement(osv.osv):
             voucher_obj.write(cr, uid, [st_line.voucher_id.id], {'number': next_number}, context=context)
             if st_line.voucher_id.state == 'cancel':
                 voucher_obj.action_cancel_draft(cr, uid, [st_line.voucher_id.id], context=context)
-            wf_service.trg_validate(uid, 'account.voucher', st_line.voucher_id.id, 'proforma_voucher', cr)
+            voucher_obj.signal_proforma_voucher(cr, uid, [st_line.voucher_id.id])
 
             v = voucher_obj.browse(cr, uid, st_line.voucher_id.id, context=context)
             bank_st_line_obj.write(cr, uid, [st_line_id], {
diff --git a/addons/account_voucher/test/case1_usd_usd.yml b/addons/account_voucher/test/case1_usd_usd.yml
index 0f4c2058fc7..fd1945691ba 100644
--- a/addons/account_voucher/test/case1_usd_usd.yml
+++ b/addons/account_voucher/test/case1_usd_usd.yml
@@ -182,10 +182,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'First payment: Case 1 USD/USD'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my first voucher is valid
 -
@@ -279,10 +277,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'Second payment: Case 1'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my second voucher is valid
 -
diff --git a/addons/account_voucher/test/case2_suppl_usd_eur.yml b/addons/account_voucher/test/case2_suppl_usd_eur.yml
index b32228032d3..91fb99f6360 100644
--- a/addons/account_voucher/test/case2_suppl_usd_eur.yml
+++ b/addons/account_voucher/test/case2_suppl_usd_eur.yml
@@ -161,10 +161,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'First payment: Case 2 SUPPL USD/EUR'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my voucher is valid
 -
@@ -266,10 +264,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'Second payment: Case 2 SUPPL USD/EUR'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that my voucher state is posted
 -
diff --git a/addons/account_voucher/test/case2_usd_eur_debtor_in_eur.yml b/addons/account_voucher/test/case2_usd_eur_debtor_in_eur.yml
index 275e4c58835..2afdc8ad31b 100644
--- a/addons/account_voucher/test/case2_usd_eur_debtor_in_eur.yml
+++ b/addons/account_voucher/test/case2_usd_eur_debtor_in_eur.yml
@@ -181,8 +181,7 @@
   !python {model: account.voucher}: |
     import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'First payment: Case 2 USD/EUR DR EUR'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my voucher is valid
 -
@@ -256,8 +255,7 @@
   !python {model: account.voucher}: |
     import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'Second payment: Case 2 SUPPL USD/EUR DR EUR'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that my voucher state is posted
 -
diff --git a/addons/account_voucher/test/case2_usd_eur_debtor_in_usd.yml b/addons/account_voucher/test/case2_usd_eur_debtor_in_usd.yml
index 667882e3a32..b049fc7692e 100644
--- a/addons/account_voucher/test/case2_usd_eur_debtor_in_usd.yml
+++ b/addons/account_voucher/test/case2_usd_eur_debtor_in_usd.yml
@@ -179,10 +179,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'First payment: Case 2 USD/EUR DR USD'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my voucher is valid
 -
@@ -269,10 +267,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'Second payment: Case 2 SUPPL USD/EUR DR USD'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that my voucher state is posted
 -
diff --git a/addons/account_voucher/test/case3_eur_eur.yml b/addons/account_voucher/test/case3_eur_eur.yml
index f2f9461c31e..d0b18a5231b 100644
--- a/addons/account_voucher/test/case3_eur_eur.yml
+++ b/addons/account_voucher/test/case3_eur_eur.yml
@@ -141,10 +141,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'First payment: Case 3'),('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my first voucher is valid
 -
@@ -231,10 +229,8 @@
   I confirm the voucher
 -
   !python {model: account.voucher}: |
-    import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'Second payment: Case 3'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my second voucher is valid
 -
diff --git a/addons/account_voucher/test/case4_cad_chf.yml b/addons/account_voucher/test/case4_cad_chf.yml
index bc33e387a85..e8fe4c8cf9b 100644
--- a/addons/account_voucher/test/case4_cad_chf.yml
+++ b/addons/account_voucher/test/case4_cad_chf.yml
@@ -143,8 +143,7 @@
   !python {model: account.voucher}: |
     import netsvc
     voucher = self.search(cr, uid, [('name', '=', 'First payment: Case 4'), ('partner_id', '=', ref('base.res_partner_19'))])
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher[0], 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, voucher)
 -
   I check that the move of my voucher is valid
 -
diff --git a/addons/account_voucher/test/sales_payment.yml b/addons/account_voucher/test/sales_payment.yml
index b71e42add0b..e7ed61c2cb2 100644
--- a/addons/account_voucher/test/sales_payment.yml
+++ b/addons/account_voucher/test/sales_payment.yml
@@ -61,8 +61,7 @@
     id = self.create(cr, uid, vals)
     voucher_id = self.browse(cr, uid, id)
     assert (voucher_id.state=='draft'), "Voucher is not in draft state"
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher_id.id, 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, [voucher_id.id])
 
 -
   Finally i will Confirm the state of the invoice is paid
diff --git a/addons/account_voucher/test/sales_receipt.yml b/addons/account_voucher/test/sales_receipt.yml
index cf4bc5c46d3..af10777d98a 100644
--- a/addons/account_voucher/test/sales_receipt.yml
+++ b/addons/account_voucher/test/sales_receipt.yml
@@ -65,8 +65,7 @@
     id = self.create(cr, uid, vals)
     voucher_id = self.browse(cr, uid, id)
     assert (voucher_id.state=='draft'), "Voucher is not in draft state"
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'account.voucher', voucher_id.id, 'proforma_voucher', cr)
+    self.signal_proforma_voucher(cr, uid, [voucher_id.id])
 -
   I check that move lines are reconciled meaning voucher is paid
 -
diff --git a/addons/hr_holidays/hr_holidays.py b/addons/hr_holidays/hr_holidays.py
index c7d7867911d..234897809e1 100644
--- a/addons/hr_holidays/hr_holidays.py
+++ b/addons/hr_holidays/hr_holidays.py
@@ -24,7 +24,7 @@
 import datetime
 import time
 from itertools import groupby
-from operator import itemgetter
+from operator import attrgetter, itemgetter
 
 import math
 from openerp import netsvc
@@ -370,11 +370,11 @@ class hr_holidays(osv.osv):
                         'employee_id': emp.id
                     }
                     leave_ids.append(self.create(cr, uid, vals, context=None))
-                wf_service = netsvc.LocalService("workflow")
                 for leave_id in leave_ids:
-                    wf_service.trg_validate(uid, 'hr.holidays', leave_id, 'confirm', cr)
-                    wf_service.trg_validate(uid, 'hr.holidays', leave_id, 'validate', cr)
-                    wf_service.trg_validate(uid, 'hr.holidays', leave_id, 'second_validate', cr)
+                    # TODO is it necessary to interleave the calls?
+                    self.signal_confirm(cr, uid, [leave_id])
+                    self.signal_validate(cr, uid, [leave_id])
+                    self.signal_second_validate(cr, uid, [leave_id])
         return True
 
     def holidays_confirm(self, cr, uid, ids, context=None):
@@ -404,9 +404,7 @@ class hr_holidays(osv.osv):
                 meeting_obj.unlink(cr, uid, [record.meeting_id.id])
 
             # If a category that created several holidays, cancel all related
-            wf_service = netsvc.LocalService("workflow")
-            for request in record.linked_request_ids or []:
-                wf_service.trg_validate(uid, 'hr.holidays', request.id, 'refuse', cr)
+            self.signal_refuse(cr, uid, map(attrgetter('id'), record.linked_request_ids or []))
 
         self._remove_resource_leave(cr, uid, ids, context=context)
         return True
@@ -478,10 +476,9 @@ class hr_employee(osv.osv):
             leave_id = holiday_obj.create(cr, uid, {'name': _('Leave Request for %s') % employee.name, 'employee_id': employee.id, 'holiday_status_id': status_id, 'type': 'remove', 'holiday_type': 'employee', 'number_of_days_temp': abs(diff)}, context=context)
         else:
             return False
-        wf_service = netsvc.LocalService("workflow")
-        wf_service.trg_validate(uid, 'hr.holidays', leave_id, 'confirm', cr)
-        wf_service.trg_validate(uid, 'hr.holidays', leave_id, 'validate', cr)
-        wf_service.trg_validate(uid, 'hr.holidays', leave_id, 'second_validate', cr)
+        holidays_obj.signal_confirm(cr, uid, [leave_id])
+        holidays_obj.signal_validate(cr, uid, [leave_id])
+        holidays_obj.signal_second_validate(cr, uid, [leave_id])
         return True
 
     def _get_remaining_days(self, cr, uid, ids, name, args, context=None):
diff --git a/addons/hr_holidays/test/test_hr_holiday.yml b/addons/hr_holidays/test/test_hr_holiday.yml
index f0e85d552cb..e78c2fd08bc 100644
--- a/addons/hr_holidays/test/test_hr_holiday.yml
+++ b/addons/hr_holidays/test/test_hr_holiday.yml
@@ -19,9 +19,8 @@
 -
   !python {model: hr.holidays}: |
      import netsvc
-     wf_service = netsvc.LocalService("workflow")
      self.set_to_draft(cr, uid, [ref('hr_holidays_employee1_cl')])
-     wf_service.trg_validate(uid, 'hr.holidays', ref('hr_holidays_employee1_cl'), 'confirm', cr)
+     self.signal_confirm(cr, uid, [ref('hr_holidays_employee1_cl')])
 -
   I validate the holiday request by clicking on "To Approve" button.
 -
diff --git a/addons/l10n_in_hr_payroll/l10n_in_hr_payroll.py b/addons/l10n_in_hr_payroll/l10n_in_hr_payroll.py
index 76fc1247de6..da98bbe681a 100644
--- a/addons/l10n_in_hr_payroll/l10n_in_hr_payroll.py
+++ b/addons/l10n_in_hr_payroll/l10n_in_hr_payroll.py
@@ -198,8 +198,9 @@ class hr_payslip_run(osv.osv):
             advice_id = advice_pool.create(cr, uid, advice_data, context=context)
             slip_ids = []
             for slip_id in run.slip_ids:
-                wf_service.trg_validate(uid, 'hr.payslip', slip_id.id, 'hr_verify_sheet', cr)
-                wf_service.trg_validate(uid, 'hr.payslip', slip_id.id, 'process_sheet', cr)
+                # TODO is it necessary to interleave the calls ?
+                payslip_pool.signal_hr_verify_sheet(cr, uid, [slip_id.id])
+                payslip_pool.signal_process_sheet(cr, uid, [slip_id.id])
                 slip_ids.append(slip_id.id)
 
             for slip in payslip_pool.browse(cr, uid, slip_ids, context=context):
diff --git a/addons/lunch/lunch.py b/addons/lunch/lunch.py
index 0f9033fce38..022eb5208eb 100644
--- a/addons/lunch/lunch.py
+++ b/addons/lunch/lunch.py
@@ -159,7 +159,7 @@ class lunch_order(osv.Model):
             def specific_function(cr, uid, ids, context=None):
                 return self.add_preference(cr, uid, ids, pref_id, context=context)
             return specific_function
-        return super(lunch_order,self).__getattr__(self,attr)
+        return super(lunch_order, self).__getattr__(attr)
 
     def fields_view_get(self, cr, uid, view_id=None, view_type=False, context=None, toolbar=False, submenu=False):
         """ 
diff --git a/addons/mrp_operations/mrp_operations.py b/addons/mrp_operations/mrp_operations.py
index 1ce60946f6c..a60b348559c 100644
--- a/addons/mrp_operations/mrp_operations.py
+++ b/addons/mrp_operations/mrp_operations.py
@@ -118,16 +118,15 @@ class mrp_production_workcenter_line(osv.osv):
         @param action: Action to perform.
         @return: Nothing
         """
-        wf_service = netsvc.LocalService("workflow")
         prod_obj_pool = self.pool.get('mrp.production')
         oper_obj = self.browse(cr, uid, ids)[0]
         prod_obj = oper_obj.production_id
         if action == 'start':
                if prod_obj.state =='confirmed':
                    prod_obj_pool.force_production(cr, uid, [prod_obj.id])
-                   wf_service.trg_validate(uid, 'mrp.production', prod_obj.id, 'button_produce', cr)
+                   prod_obj_pool.signal_button_produce(cr, uid, [prod_obj.id])
                elif prod_obj.state =='ready':
-                   wf_service.trg_validate(uid, 'mrp.production', prod_obj.id, 'button_produce', cr)
+                   prod_obj_pool.signal_button_produce(cr, uid, [prod_obj.id])
                elif prod_obj.state =='in_production':
                    return
                else:
@@ -143,7 +142,7 @@ class mrp_production_workcenter_line(osv.osv):
                 for production in prod_obj_pool.browse(cr, uid, [prod_obj.id], context= None):
                     if production.move_lines or production.move_created_ids:
                         prod_obj_pool.action_produce(cr,uid, production.id, production.product_qty, 'consume_produce', context = None)
-                wf_service.trg_validate(uid, 'mrp.production', oper_obj.production_id.id, 'button_produce_done', cr)
+                prod_obj_pool.signal_button_produce_done(cr, uid, [oper_obj.production_id.id])
         return
 
     def write(self, cr, uid, ids, vals, context=None, update=True):
@@ -228,23 +227,21 @@ class mrp_production(osv.osv):
         @return: Super method
         """
         obj = self.browse(cr, uid, ids)[0]
-        wf_service = netsvc.LocalService("workflow")
+        workcenter_pool = self.pool.get('mrp.production.workcenter.line')
         for workcenter_line in obj.workcenter_lines:
             if workcenter_line.state == 'draft':
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', workcenter_line.id, 'button_start_working', cr)
-            wf_service.trg_validate(uid, 'mrp.production.workcenter.line', workcenter_line.id, 'button_done', cr)
+                workcenter_pool.signal_button_start_working(cr, uid, [workcenter_line.id])
+            workcenter_pool.signal_button_done(cr, uid, [workcenter_line.id])
         return super(mrp_production,self).action_production_end(cr, uid, ids)
 
     def action_in_production(self, cr, uid, ids):
         """ Changes state to In Production and writes starting date.
         @return: True
         """
-        obj = self.browse(cr, uid, ids)[0]
         workcenter_pool = self.pool.get('mrp.production.workcenter.line')
-        wf_service = netsvc.LocalService("workflow")
         for prod in self.browse(cr, uid, ids):
             if prod.workcenter_lines:
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', prod.workcenter_lines[0].id, 'button_start_working', cr)
+                workcenter_pool.signal_button_start_working(cr, uid, [prod.workcenter_lines[0].id])
         return super(mrp_production,self).action_in_production(cr, uid, ids)
     
     def action_cancel(self, cr, uid, ids, context=None):
@@ -252,9 +249,8 @@ class mrp_production(osv.osv):
         @return: Super method
         """
         obj = self.browse(cr, uid, ids,context=context)[0]
-        wf_service = netsvc.LocalService("workflow")
         for workcenter_line in obj.workcenter_lines:
-            wf_service.trg_validate(uid, 'mrp.production.workcenter.line', workcenter_line.id, 'button_cancel', cr)
+            workcenter_pool.signal_button_cancel(cr, uid, [workcenter_line.id])
         return super(mrp_production,self).action_cancel(cr,uid,ids,context=context)
 
     def _compute_planned_workcenter(self, cr, uid, ids, context=None, mini=False):
@@ -503,35 +499,35 @@ class mrp_operations_operation(osv.osv):
         return super(mrp_operations_operation, self).write(cr, uid, ids, vals, context=context)
 
     def create(self, cr, uid, vals, context=None):
+        workcenter_pool = self.pool.get('mrp.production.workcenter.line')
         wf_service = netsvc.LocalService('workflow')
         code_ids=self.pool.get('mrp_operations.operation.code').search(cr,uid,[('id','=',vals['code_id'])])
         code=self.pool.get('mrp_operations.operation.code').browse(cr, uid, code_ids, context=context)[0]
-        wc_op_id=self.pool.get('mrp.production.workcenter.line').search(cr,uid,[('workcenter_id','=',vals['workcenter_id']),('production_id','=',vals['production_id'])])
+        wc_op_id=workcenter_pool.search(cr,uid,[('workcenter_id','=',vals['workcenter_id']),('production_id','=',vals['production_id'])])
         if code.start_stop in ('start','done','pause','cancel','resume'):
             if not wc_op_id:
                 production_obj=self.pool.get('mrp.production').browse(cr, uid, vals['production_id'], context=context)
-                wc_op_id.append(self.pool.get('mrp.production.workcenter.line').create(cr,uid,{'production_id':vals['production_id'],'name':production_obj.product_id.name,'workcenter_id':vals['workcenter_id']}))
+                wc_op_id.append(workcenter_pool.create(cr,uid,{'production_id':vals['production_id'],'name':production_obj.product_id.name,'workcenter_id':vals['workcenter_id']}))
             if code.start_stop=='start':
-                self.pool.get('mrp.production.workcenter.line').action_start_working(cr,uid,wc_op_id)
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', wc_op_id[0], 'button_start_working', cr)
-
+                workcenter_pool.action_start_working(cr,uid,wc_op_id)
+                workcenter_pool.signal_button_start_working(cr, uid, [wc_op_id[0]])
 
             if code.start_stop=='done':
-                self.pool.get('mrp.production.workcenter.line').action_done(cr,uid,wc_op_id)
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', wc_op_id[0], 'button_done', cr)
+                workcenter_pool.action_done(cr,uid,wc_op_id)
+                workcenter_pool.signal_button_done(cr, uid, [wc_op_id[0]])
                 self.pool.get('mrp.production').write(cr,uid,vals['production_id'],{'date_finished':datetime.now().strftime('%Y-%m-%d %H:%M:%S')})
 
             if code.start_stop=='pause':
-                self.pool.get('mrp.production.workcenter.line').action_pause(cr,uid,wc_op_id)
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', wc_op_id[0], 'button_pause', cr)
+                workcenter_pool.action_pause(cr,uid,wc_op_id)
+                workcenter_pool.signal_button_pause(cr, uid, [wc_op_id[0]])
 
             if code.start_stop=='resume':
-                self.pool.get('mrp.production.workcenter.line').action_resume(cr,uid,wc_op_id)
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', wc_op_id[0], 'button_resume', cr)
+                workcenter_pool.action_resume(cr,uid,wc_op_id)
+                workcenter_pool.signal_button_resume(cr, uid, [wc_op_id[0]])
 
             if code.start_stop=='cancel':
-                self.pool.get('mrp.production.workcenter.line').action_cancel(cr,uid,wc_op_id)
-                wf_service.trg_validate(uid, 'mrp.production.workcenter.line', wc_op_id[0], 'button_cancel', cr)
+                workcenter_pool.action_cancel(cr,uid,wc_op_id)
+                workcenter_pool.signal_button_cancel(cr, uid, [wc_op_id[0]])
 
         if not self.check_operation(cr, uid, vals):
             return
diff --git a/addons/mrp_operations/test/workcenter_operations.yml b/addons/mrp_operations/test/workcenter_operations.yml
index c1449657967..4754bb463ff 100644
--- a/addons/mrp_operations/test/workcenter_operations.yml
+++ b/addons/mrp_operations/test/workcenter_operations.yml
@@ -39,62 +39,48 @@
   Production start on first work center, so I start work operation on first work center.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_start_working', cr)
+    self.pool.get('mrp.production.workcenter.line').signal_button_start_working(cr, uid, [order.workcenter_lines[0].id])
 -
   Now I pause first work operation due to technical fault of work center.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_pause', cr)
+    self.pool.get('mrp.production.workcenter.line').signal_button_pause(cr, uid, [order.workcenter_lines[0].id])
 -
   I resume first work operation.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_resume', cr)
+    self.pool.get('mrp.production.workcenter.line').signal_button_resume(cr, uid, [order.workcenter_lines[0].id])
     
 -
   I cancel first work operation.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_cancel', cr)
+    self.pool.get('mrp.production.workcenter.line').signal_button_cancel(cr, uid, [order.workcenter_lines[0].id])
 -
   I reset first work operation and start after resolving techninal fault of work center.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_draft', cr)
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_start_working', cr)
+    self.pool.get('mrp.production.workcenter.line').signal_button_draft(cr, uid, [order.workcenter_lines[0].id])
+    self.pool.get('mrp.production.workcenter.line').signal_button_start_working(cr, uid, [order.workcenter_lines[0].id])
 -
   I close first work operation as this work center completed its process.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
-    wf_service.trg_validate(uid, 'mrp.production.workcenter.line', order.workcenter_lines[0].id, 'button_done', cr)
+    self.pool.get('mrp.production.workcenter.line').signal_button_done(cr, uid, [order.workcenter_lines[0].id])
 -
   Now I close other operations one by one which are in start state.
 -
   !python {model: mrp.production}: |
-    import netsvc
     order = self.browse(cr, uid, ref("mrp.mrp_production_1"), context=context)
-    wf_service = netsvc.LocalService("workflow")
     for work_line in order.workcenter_lines[1:]:
-        wf_service.trg_validate(uid, 'mrp.production.workcenter.line', work_line.id, 'button_start_working', cr)
-        wf_service.trg_validate(uid, 'mrp.production.workcenter.line', work_line.id, 'button_done', cr)
+        self.pool.get('mrp.production.workcenter.line').signal_button_start_working(cr, uid, [work_line.id])
+        self.pool.get('mrp.production.workcenter.line').signal_button_done(cr, uid, [work_line.id])
 
 -
   I check that the production order is now done.
diff --git a/addons/procurement/procurement.py b/addons/procurement/procurement.py
index 50efe0f500e..21c260b99cd 100644
--- a/addons/procurement/procurement.py
+++ b/addons/procurement/procurement.py
@@ -19,10 +19,12 @@
 #
 ##############################################################################
 
+from operator import attrgetter
+import time
+
 from openerp.osv import fields, osv
 from openerp.tools.translate import _
 from openerp import netsvc
-import time
 import openerp.addons.decimal_precision as dp
 
 # Procurement
@@ -42,7 +44,6 @@ class mrp_property_group(osv.osv):
         'name': fields.char('Property Group', size=64, required=True),
         'description': fields.text('Description'),
     }
-mrp_property_group()
 
 class mrp_property(osv.osv):
     """
@@ -59,7 +60,6 @@ class mrp_property(osv.osv):
     _defaults = {
         'composition': lambda *a: 'min',
     }
-mrp_property()
 
 class StockMove(osv.osv):
     _inherit = 'stock.move'
@@ -72,7 +72,6 @@ class StockMove(osv.osv):
         default['procurements'] = []
         return super(StockMove, self).copy(cr, uid, id, default, context=context)
 
-StockMove()
 
 class procurement_order(osv.osv):
     """
@@ -456,15 +455,13 @@ class procurement_order(osv.osv):
 
 class StockPicking(osv.osv):
     _inherit = 'stock.picking'
-    def test_finished(self, cursor, user, ids):
+    def test_finished(self, cr, uid, ids):
         wf_service = netsvc.LocalService("workflow")
-        res = super(StockPicking, self).test_finished(cursor, user, ids)
-        for picking in self.browse(cursor, user, ids):
+        res = super(StockPicking, self).test_finished(cr, uid, ids)
+        for picking in self.browse(cr, uid, ids):
             for move in picking.move_lines:
                 if move.state == 'done' and move.procurements:
-                    for procurement in move.procurements:
-                        wf_service.trg_validate(user, 'procurement.order',
-                            procurement.id, 'button_check', cursor)
+                    self.pool.get('procurement.order').signal_button_check(cr, uid, map(attrgetter('id'), move.procurements))
         return res
 
 class stock_warehouse_orderpoint(osv.osv):
diff --git a/addons/procurement/schedulers.py b/addons/procurement/schedulers.py
index 3cb34d6bdff..76b31cc6da3 100644
--- a/addons/procurement/schedulers.py
+++ b/addons/procurement/schedulers.py
@@ -62,8 +62,7 @@ class procurement_order(osv.osv):
             procurement_obj = self.pool.get('procurement.order')
             if not ids:
                 ids = procurement_obj.search(cr, uid, [('state', '=', 'exception')], order="date_planned")
-            for id in ids:
-                wf_service.trg_validate(uid, 'procurement.order', id, 'button_restart', cr)
+            self.signal_button_restart(cr, uid, ids)
             if use_new_cursor:
                 cr.commit()
             company = self.pool.get('res.users').browse(cr, uid, uid, context=context).company_id
@@ -78,7 +77,7 @@ class procurement_order(osv.osv):
                 ids = procurement_obj.search(cr, uid, [('state', '=', 'confirmed'), ('procure_method', '=', 'make_to_order')], offset=offset, limit=500, order='priority, date_planned', context=context)
                 for proc in procurement_obj.browse(cr, uid, ids, context=context):
                     if maxdate >= proc.date_planned:
-                        wf_service.trg_validate(uid, 'procurement.order', proc.id, 'button_check', cr)
+                        self.signal_button_check(cr, uid, [proc.id])
                     else:
                         offset += 1
                         report_later += 1
@@ -100,7 +99,7 @@ class procurement_order(osv.osv):
                 ids = procurement_obj.search(cr, uid, [('state', '=', 'confirmed'), ('procure_method', '=', 'make_to_stock')], offset=offset)
                 for proc in procurement_obj.browse(cr, uid, ids):
                     if maxdate >= proc.date_planned:
-                        wf_service.trg_validate(uid, 'procurement.order', proc.id, 'button_check', cr)
+                        self.signal_button_check(cr, uid, [proc.id])
                         report_ids.append(proc.id)
                     else:
                         report_later += 1
@@ -178,8 +177,8 @@ class procurement_order(osv.osv):
                 proc_id = proc_obj.create(cr, uid,
                             self._prepare_automatic_op_procurement(cr, uid, product, warehouse, location_id, context=context),
                             context=context)
-                wf_service.trg_validate(uid, 'procurement.order', proc_id, 'button_confirm', cr)
-                wf_service.trg_validate(uid, 'procurement.order', proc_id, 'button_check', cr)
+                self.signal_button_confirm(cr, uid, [proc_id])
+                self.signal_button_check(cr, uid, [proc_id])
         return True
 
     def _get_orderpoint_date_planned(self, cr, uid, orderpoint, start_date, context=None):
@@ -254,7 +253,7 @@ class procurement_order(osv.osv):
                             to_generate = qty
                             for proc_data in procure_datas:
                                 if to_generate >= proc_data['product_qty']:
-                                    wf_service.trg_validate(uid, 'procurement.order', proc_data['id'], 'button_confirm', cr)
+                                    self.signal_button_confirm(cr, uid, [proc_data['id']])
                                     procurement_obj.write(cr, uid, [proc_data['id']],  {'origin': op.name}, context=context)
                                     to_generate -= proc_data['product_qty']
                                 if not to_generate:
@@ -265,10 +264,8 @@ class procurement_order(osv.osv):
                         proc_id = procurement_obj.create(cr, uid,
                                                          self._prepare_orderpoint_procurement(cr, uid, op, qty, context=context),
                                                          context=context)
-                        wf_service.trg_validate(uid, 'procurement.order', proc_id,
-                                'button_confirm', cr)
-                        wf_service.trg_validate(uid, 'procurement.order', proc_id,
-                                'button_check', cr)
+                        self.signal_button_confirm(cr, uid, [proc_id])
+                        self.signal_button_check(cr, uid, [proc_id])
                         orderpoint_obj.write(cr, uid, [op.id],
                                 {'procurement_id': proc_id}, context=context)
             offset += len(ids)
@@ -279,6 +276,4 @@ class procurement_order(osv.osv):
             cr.close()
         return {}
 
-procurement_order()
-
 # vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index 799601acb64..a45da4a2d61 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -22,6 +22,7 @@
 import time
 from datetime import datetime
 from dateutil.relativedelta import relativedelta
+from operator import attrgetter
 
 from openerp.osv import fields, osv
 from openerp import netsvc
@@ -260,9 +261,7 @@ class purchase_order(osv.osv):
                 raise osv.except_osv(_('Invalid Action!'), _('In order to delete a purchase order, you must cancel it first.'))
 
         # automatically sending subflow.delete upon deletion
-        wf_service = netsvc.LocalService("workflow")
-        for id in unlink_ids:
-            wf_service.trg_validate(uid, 'purchase.order', id, 'purchase_cancel', cr)
+        self.signal_purchase_cancel(cr, uid, unlink_ids)
 
         return super(purchase_order, self).unlink(cr, uid, unlink_ids, context=context)
 
@@ -439,8 +438,7 @@ class purchase_order(osv.osv):
         This function prints the request for quotation and mark it as sent, so that we can see more easily the next step of the workflow
         '''
         assert len(ids) == 1, 'This option should only be used for a single id at a time'
-        wf_service = netsvc.LocalService("workflow")
-        wf_service.trg_validate(uid, 'purchase.order', ids[0], 'send_rfq', cr)
+        self.signal_send_rfq(cr, uid, ids)
         datas = {
                  'model': 'purchase.order',
                  'ids': ids,
@@ -489,8 +487,8 @@ class purchase_order(osv.osv):
         wf_service = netsvc.LocalService("workflow")
         for p_id in ids:
             # Deleting the existing instance of workflow for PO
-            wf_service.trg_delete(uid, 'purchase.order', p_id, cr)
-            wf_service.trg_create(uid, 'purchase.order', p_id, cr)
+            self.delete_workflow(cr, uid, [p_id]) # TODO is it necessary to interleave the calls?
+            self.create_workflow(cr, uid, [p_id])
         return True
 
     def action_invoice_create(self, cr, uid, ids, context=None):
@@ -571,26 +569,24 @@ class purchase_order(osv.osv):
         return False
 
     def action_cancel(self, cr, uid, ids, context=None):
-        wf_service = netsvc.LocalService("workflow")
         for purchase in self.browse(cr, uid, ids, context=context):
             for pick in purchase.picking_ids:
                 if pick.state not in ('draft','cancel'):
                     raise osv.except_osv(
                         _('Unable to cancel this purchase order.'),
                         _('First cancel all receptions related to this purchase order.'))
-            for pick in purchase.picking_ids:
-                wf_service.trg_validate(uid, 'stock.picking', pick.id, 'button_cancel', cr)
+            self.pool.get('stock.picking') \
+                .signal_button_cancel(cr, uid, map(attrgetter('id'), purchase.picking_ids))
             for inv in purchase.invoice_ids:
                 if inv and inv.state not in ('cancel','draft'):
                     raise osv.except_osv(
                         _('Unable to cancel this purchase order.'),
                         _('You must first cancel all receptions related to this purchase order.'))
-                if inv:
-                    wf_service.trg_validate(uid, 'account.invoice', inv.id, 'invoice_cancel', cr)
+            self.pool.get('account.invoice') \
+                .signal_invoice_cancel(cr, uid, map(attrgetter('id'), purchase.invoice_ids))
         self.write(cr,uid,ids,{'state':'cancel'})
 
-        for (id, name) in self.name_get(cr, uid, ids):
-            wf_service.trg_validate(uid, 'purchase.order', id, 'purchase_cancel', cr)
+        self.signal_purchase_cancel(cr, uid, ids)
         return True
 
     def _prepare_order_picking(self, cr, uid, order, context=None):
@@ -648,11 +644,11 @@ class purchase_order(osv.osv):
                                will be added. A new picking will be created if omitted.
         :return: list of IDs of pickings used/created for the given order lines (usually just one)
         """
+        stock_picking = self.pool.get('stock.picking')
         if not picking_id:
-            picking_id = self.pool.get('stock.picking').create(cr, uid, self._prepare_order_picking(cr, uid, order, context=context))
+            picking_id = stock_picking.create(cr, uid, self._prepare_order_picking(cr, uid, order, context=context))
         todo_moves = []
         stock_move = self.pool.get('stock.move')
-        wf_service = netsvc.LocalService("workflow")
         for order_line in order_lines:
             if not order_line.product_id:
                 continue
@@ -663,7 +659,7 @@ class purchase_order(osv.osv):
                 todo_moves.append(move)
         stock_move.action_confirm(cr, uid, todo_moves)
         stock_move.force_assign(cr, uid, todo_moves)
-        wf_service.trg_validate(uid, 'stock.picking', picking_id, 'button_confirm', cr)
+        stock_picking.signal_button_confirm(cr, uid, [picking_id])
         return [picking_id]
 
     def action_picking_create(self, cr, uid, ids, context=None):
@@ -714,7 +710,6 @@ class purchase_order(osv.osv):
 
         """
         #TOFIX: merged order line should be unlink
-        wf_service = netsvc.LocalService("workflow")
         def make_key(br, fields):
             list_key = []
             for field in fields:
@@ -782,6 +777,7 @@ class purchase_order(osv.osv):
 
         allorders = []
         orders_info = {}
+        wf_service = netsvc.LocalService("workflow")
         for order_key, (order_data, old_ids) in new_orders.iteritems():
             # skip merges with only one order
             if len(old_ids) < 2:
@@ -801,8 +797,8 @@ class purchase_order(osv.osv):
 
             # make triggers pointing to the old orders point to the new order
             for old_id in old_ids:
-                wf_service.trg_redirect(uid, 'purchase.order', old_id, neworder_id, cr)
-                wf_service.trg_validate(uid, 'purchase.order', old_id, 'purchase_cancel', cr)
+                self.redirect_workflow(cr, uid, [(old_id, neworder_id)])
+                self.signal_purchase_cancel(cr, uid, [old_id]) # TODO Is it necessary to interleave the calls?
         return orders_info
 
 
@@ -1169,8 +1165,7 @@ class mail_mail(osv.Model):
 
     def _postprocess_sent_message(self, cr, uid, mail, context=None):
         if mail.model == 'purchase.order':
-            wf_service = netsvc.LocalService("workflow")
-            wf_service.trg_validate(uid, 'purchase.order', mail.res_id, 'send_rfq', cr)
+            self.pool.get('purchase.order').signal_send_rfq(cr, uid, [mail.res_id])
         return super(mail_mail, self)._postprocess_sent_message(cr, uid, mail=mail, context=context)
 
 
@@ -1192,8 +1187,7 @@ class mail_compose_message(osv.Model):
         context = context or {}
         if context.get('default_model') == 'purchase.order' and context.get('default_res_id'):
             context = dict(context, mail_post_autofollow=True)
-            wf_service = netsvc.LocalService("workflow")
-            wf_service.trg_validate(uid, 'purchase.order', context['default_res_id'], 'send_rfq', cr)
+            self.pool.get('purchase.order').signal_send_rfq(cr, uid, [context['default_res_id']])
         return super(mail_compose_message, self).send_mail(cr, uid, ids, context=context)
 
 # vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
diff --git a/addons/purchase/test/process/rfq2order2done.yml b/addons/purchase/test/process/rfq2order2done.yml
index 4bf55d61973..be68a8ca01e 100644
--- a/addons/purchase/test/process/rfq2order2done.yml
+++ b/addons/purchase/test/process/rfq2order2done.yml
@@ -62,8 +62,7 @@
     import netsvc
     invoice_ids = [x.id for x in self.browse(cr, uid, ref("purchase_order_1")).invoice_ids]
     wf_service = netsvc.LocalService("workflow")
-    for invoice in invoice_ids:
-      wf_service.trg_validate(uid, 'account.invoice', invoice, 'invoice_open', cr)
+    self.pool.get('account.invoice').signal_invoice_open(cr, uid, invoice_ids)
 -
   I check that purchase order is invoiced.
 -
diff --git a/addons/stock/stock.py b/addons/stock/stock.py
index 7198c89e286..2d351d9302e 100644
--- a/addons/stock/stock.py
+++ b/addons/stock/stock.py
@@ -759,10 +759,9 @@ class stock_picking(osv.osv):
         """ Changes state of picking to available if all moves are confirmed.
         @return: True
         """
-        wf_service = netsvc.LocalService("workflow")
         for pick in self.browse(cr, uid, ids):
             if pick.state == 'draft':
-                wf_service.trg_validate(uid, 'stock.picking', pick.id, 'button_confirm', cr)
+                self.signal_button_confirm(cr, uid, [pick.id])
             move_ids = [x.id for x in pick.move_lines if x.state == 'confirmed']
             if not move_ids:
                 raise osv.except_osv(_('Warning!'),_('Not enough stock, unable to reserve the products.'))
@@ -784,12 +783,10 @@ class stock_picking(osv.osv):
         """ Confirms picking directly from draft state.
         @return: True
         """
-        wf_service = netsvc.LocalService("workflow")
         for pick in self.browse(cr, uid, ids):
             if not pick.move_lines:
                 raise osv.except_osv(_('Error!'),_('You cannot process picking without stock moves.'))
-            wf_service.trg_validate(uid, 'stock.picking', pick.id,
-                'button_confirm', cr)
+            self.signal_button_confirm(cr, uid, [pick.id])
         return True
 
     def draft_validate(self, cr, uid, ids, context=None):
@@ -1345,18 +1342,18 @@ class stock_picking(osv.osv):
 
             # At first we confirm the new picking (if necessary)
             if new_picking:
-                wf_service.trg_validate(uid, 'stock.picking', new_picking, 'button_confirm', cr)
+                self.signal_button_confirm(cr, uid, [new_picking])
                 # Then we finish the good picking
                 self.write(cr, uid, [pick.id], {'backorder_id': new_picking})
                 self.action_move(cr, uid, [new_picking], context=context)
-                wf_service.trg_validate(uid, 'stock.picking', new_picking, 'button_done', cr)
+                self.signal_button_done(cr, uid, [new_picking])
                 wf_service.trg_write(uid, 'stock.picking', pick.id, cr)
                 delivered_pack_id = new_picking
                 back_order_name = self.browse(cr, uid, delivered_pack_id, context=context).name
                 self.message_post(cr, uid, ids, body=_("Back order <em>%s</em> has been <b>created</b>.") % (back_order_name), context=context)
             else:
                 self.action_move(cr, uid, [pick.id], context=context)
-                wf_service.trg_validate(uid, 'stock.picking', pick.id, 'button_done', cr)
+                self.signal_button_done(cr, uid, [pick.id])
                 delivered_pack_id = pick.id
 
             delivered_pack = self.browse(cr, uid, delivered_pack_id, context=context)
@@ -2037,7 +2034,6 @@ class stock_move(osv.osv):
         res_obj = self.pool.get('res.company')
         location_obj = self.pool.get('stock.location')
         move_obj = self.pool.get('stock.move')
-        wf_service = netsvc.LocalService("workflow")
         new_moves = []
         if context is None:
             context = {}
@@ -2073,7 +2069,7 @@ class stock_move(osv.osv):
                 })
                 new_moves.append(self.browse(cr, uid, [new_id])[0])
             if pickid:
-                wf_service.trg_validate(uid, 'stock.picking', pickid, 'button_confirm', cr)
+                self.signal_button_confirm(cr, uid, [pickid])
         if new_moves:
             new_moves += self.create_chained_picking(cr, uid, new_moves, context)
         return new_moves
@@ -2195,6 +2191,7 @@ class stock_move(osv.osv):
             return True
         if context is None:
             context = {}
+        wf_service = netsvc.LocalService("workflow")
         pickings = set()
         for move in self.browse(cr, uid, ids, context=context):
             if move.state in ('confirmed', 'waiting', 'assigned', 'draft'):
@@ -2203,7 +2200,6 @@ class stock_move(osv.osv):
             if move.move_dest_id and move.move_dest_id.state == 'waiting':
                 self.write(cr, uid, [move.move_dest_id.id], {'state': 'assigned'})
                 if context.get('call_unlink',False) and move.move_dest_id.picking_id:
-                    wf_service = netsvc.LocalService("workflow")
                     wf_service.trg_write(uid, 'stock.picking', move.move_dest_id.picking_id.id, cr)
         self.write(cr, uid, ids, {'state': 'cancel', 'move_dest_id': False})
         if not context.get('call_unlink',False):
@@ -2211,7 +2207,6 @@ class stock_move(osv.osv):
                 if all(move.state == 'cancel' for move in pick.move_lines):
                     self.pool.get('stock.picking').write(cr, uid, [pick.id], {'state': 'cancel'})
 
-        wf_service = netsvc.LocalService("workflow")
         for id in ids:
             wf_service.trg_trigger(uid, 'stock.move', id, cr)
         return True
@@ -2633,7 +2628,6 @@ class stock_move(osv.osv):
         product_obj = self.pool.get('product.product')
         currency_obj = self.pool.get('res.currency')
         uom_obj = self.pool.get('product.uom')
-        wf_service = netsvc.LocalService("workflow")
 
         if context is None:
             context = {}
@@ -2734,7 +2728,7 @@ class stock_move(osv.osv):
                 res = cr.fetchall()
                 if len(res) == len(move.picking_id.move_lines):
                     picking_obj.action_move(cr, uid, [move.picking_id.id])
-                    wf_service.trg_validate(uid, 'stock.picking', move.picking_id.id, 'button_done', cr)
+                    picking_obj.signal_button_done(cr, uid, [move.picking_id.id])
 
         return [move.id for move in complete]
 
diff --git a/addons/stock/wizard/stock_return_picking.py b/addons/stock/wizard/stock_return_picking.py
index 7c6f0655e7a..bc149f86176 100644
--- a/addons/stock/wizard/stock_return_picking.py
+++ b/addons/stock/wizard/stock_return_picking.py
@@ -151,7 +151,6 @@ class stock_return_picking(osv.osv_memory):
         data_obj = self.pool.get('stock.return.picking.memory')
         act_obj = self.pool.get('ir.actions.act_window')
         model_obj = self.pool.get('ir.model.data')
-        wf_service = netsvc.LocalService("workflow")
         pick = pick_obj.browse(cr, uid, record_id, context=context)
         data = self.read(cr, uid, ids[0], context=context)
         date_cur = time.strftime('%Y-%m-%d %H:%M:%S')
@@ -206,7 +205,7 @@ class stock_return_picking(osv.osv_memory):
 
         if set_invoice_state_to_none:
             pick_obj.write(cr, uid, [pick.id], {'invoice_state':'none'}, context=context)
-        wf_service.trg_validate(uid, 'stock.picking', new_picking, 'button_confirm', cr)
+        pick_obj.signal_button_confirm(cr, uid, [new_picking])
         pick_obj.force_assign(cr, uid, [new_picking], context)
         # Update view id in context, lp:702939
         model_list = {
diff --git a/addons/stock_location/procurement_pull.py b/addons/stock_location/procurement_pull.py
index eb5235d35ba..9f5dfb77375 100644
--- a/addons/stock_location/procurement_pull.py
+++ b/addons/stock_location/procurement_pull.py
@@ -49,7 +49,6 @@ class procurement_order(osv.osv):
         proc_obj = self.pool.get('procurement.order')
         move_obj = self.pool.get('stock.move')
         picking_obj=self.pool.get('stock.picking')
-        wf_service = netsvc.LocalService("workflow")
         for proc in proc_obj.browse(cr, uid, ids, context=context):
             line = None
             for line in proc.product_id.flow_pull_ids:
@@ -109,9 +108,8 @@ class procurement_order(osv.osv):
                 'procure_method': line.procure_method,
                 'move_id': move_id,
             })
-            wf_service = netsvc.LocalService("workflow")
-            wf_service.trg_validate(uid, 'stock.picking', picking_id, 'button_confirm', cr)
-            wf_service.trg_validate(uid, 'procurement.order', proc_id, 'button_confirm', cr)
+            self.pool.get('stock.picking').signal_button_confirm(cr, uid, [picking_id])
+            self.signal_button_confirm(cr, uid, [proc_id])
             if proc.move_id:
                 move_obj.write(cr, uid, [proc.move_id.id],
                     {'location_id':proc.location_id.id})
@@ -119,9 +117,8 @@ class procurement_order(osv.osv):
             self.write(cr, uid, [proc.id], {'state':'running', 'message': msg})
             self.message_post(cr, uid, [proc.id], body=msg, context=context)
             # trigger direct processing (the new procurement shares the same planned date as the original one, which is already being processed)
-            wf_service.trg_validate(uid, 'procurement.order', proc_id, 'button_check', cr)
+            self.signal_button_check(cr, uid, [proc_id]) # TODO is it necessary to interleave the calls?
         return False
 
-procurement_order()
 
 # vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4: