diff --git a/addons/account/account_invoice_view.xml b/addons/account/account_invoice_view.xml
index ed45c705674..be431c9b2e7 100644
--- a/addons/account/account_invoice_view.xml
+++ b/addons/account/account_invoice_view.xml
@@ -53,8 +53,8 @@
                 <form string="Invoice Line">
                     <notebook>
                         <page string="Line">
-                            <field name="product_id" on_change="product_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.address_invoice_id, parent.currency_id, {'company_id': parent.company_id})"/>
-                            <field name="uos_id"  on_change="uos_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.address_invoice_id, parent.currency_id, {'company_id': parent.company_id})"/>
+                            <field name="product_id" on_change="product_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.address_invoice_id, parent.currency_id, context, parent.company_id)"/>
+                            <field name="uos_id"  on_change="uos_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.address_invoice_id, parent.currency_id, context, parent.company_id)"/>
                             <field name="quantity"/>
                             <field name="price_unit"/>
                             <field name="discount" groups="base.group_extended"/>
@@ -175,7 +175,7 @@
                             <field name="check_total" required="2"/>
                             <field colspan="4" default_get="{'check_total': check_total, 'invoice_line': invoice_line, 'address_invoice_id': address_invoice_id, 'partner_id': partner_id, 'price_type': 'price_type' in dir() and price_type or False}" name="invoice_line" context="{'type': type}" nolabel="1">
                                 <tree string="Invoice lines">
-                                    <field name="product_id" on_change="product_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.address_invoice_id, parent.currency_id, {'company_id': parent.company_id})"/>
+                                    <field name="product_id" on_change="product_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.address_invoice_id, parent.currency_id, context, parent.company_id)"/>
                                     <field domain="[('company_id', '=', parent.company_id), ('journal_id', '=', parent.journal_id), ('type', '&lt;&gt;', 'view')]" name="account_id" on_change="onchange_account_id(parent.fiscal_position,account_id)"/>
                                     <field name="invoice_line_tax_id" view_mode="2" context="{'type':parent.type}" domain="[('parent_id','=',False)]"/>
                                     <field domain="[('type','&lt;&gt;','view'), ('company_id', '=', parent.company_id), ('parent_id', '!=', False)]" name="account_analytic_id" groups="analytic.group_analytic_accounting"/>
diff --git a/addons/account/invoice.py b/addons/account/invoice.py
index 8b1b2a0edda..09e8304340c 100644
--- a/addons/account/invoice.py
+++ b/addons/account/invoice.py
@@ -1312,10 +1312,12 @@ class account_invoice_line(osv.osv):
             res['arch'] = etree.tostring(doc)
         return res
 
-    def product_id_change(self, cr, uid, ids, product, uom, qty=0, name='', type='out_invoice', partner_id=False, fposition_id=False, price_unit=False, address_invoice_id=False, currency_id=False, context=None):
+    def product_id_change(self, cr, uid, ids, product, uom, qty=0, name='', type='out_invoice', partner_id=False, fposition_id=False, price_unit=False, address_invoice_id=False, currency_id=False, context=None, company_id=None):
         if context is None:
             context = {}
-        company_id = context.get('company_id',False)
+        company_id = company_id if company_id != None else context.get('company_id',False)
+        context = dict(context)
+        context.update({'company_id': company_id})
         if not partner_id:
             raise osv.except_osv(_('No Partner Defined !'),_("You must first select a partner !") )
         if not product:
@@ -1386,7 +1388,12 @@ class account_invoice_line(osv.osv):
                 res_final['value']['price_unit'] = new_price
         return res_final
 
-    def uos_id_change(self, cr, uid, ids, product, uom, qty=0, name='', type='out_invoice', partner_id=False, fposition_id=False, price_unit=False, address_invoice_id=False, currency_id=False, context=None):
+    def uos_id_change(self, cr, uid, ids, product, uom, qty=0, name='', type='out_invoice', partner_id=False, fposition_id=False, price_unit=False, address_invoice_id=False, currency_id=False, context=None, company_id=None):
+        if context is None:
+            context = {}
+        company_id = company_id if company_id != None else context.get('company_id',False)
+        context = dict(context)
+        context.update({'company_id': company_id})
         warning = {}
         res = self.product_id_change(cr, uid, ids, product, uom, qty, name, type, partner_id, fposition_id, price_unit, address_invoice_id, currency_id, context=context)
         if 'uos_id' in res['value']:
diff --git a/addons/account_voucher/account_voucher.py b/addons/account_voucher/account_voucher.py
index dee3d81832b..0e85904dcd7 100644
--- a/addons/account_voucher/account_voucher.py
+++ b/addons/account_voucher/account_voucher.py
@@ -150,11 +150,13 @@ class account_voucher(osv.osv):
             credit += l['amount']
         return abs(amount - abs(credit - debit))
 
-    def onchange_line_ids(self, cr, uid, ids, line_dr_ids, line_cr_ids, amount):
+    def onchange_line_ids(self, cr, uid, ids, line_dr_ids, line_cr_ids, amount, context=None):
+        context = context or {}
         if not line_dr_ids and not line_cr_ids:
             return {'value':{}}
-        line_dr_ids = [x[2] for x in line_dr_ids]
-        line_cr_ids = [x[2] for x in line_cr_ids]
+        line_osv = self.pool.get("account.voucher.line")
+        line_dr_ids = resolve_o2m_operations(cr, uid, line_osv, line_dr_ids, ['amount'], context)
+        line_cr_ids = resolve_o2m_operations(cr, uid, line_osv, line_cr_ids, ['amount'], context)
         return {'value': {'writeoff_amount': self._compute_writeoff_amount(cr, uid, line_dr_ids, line_cr_ids, amount)}}
 
     def _get_writeoff_amount(self, cr, uid, ids, name, args, context=None):
@@ -294,22 +296,24 @@ class account_voucher(osv.osv):
         return True
 
     def onchange_price(self, cr, uid, ids, line_ids, tax_id, partner_id=False, context=None):
+        context = context or {}
         tax_pool = self.pool.get('account.tax')
         partner_pool = self.pool.get('res.partner')
         position_pool = self.pool.get('account.fiscal.position')
+        line_pool = self.pool.get('account.voucher.line')
         res = {
             'tax_amount': False,
             'amount': False,
         }
         voucher_total = 0.0
-        voucher_line_ids = []
+
+        line_ids = resolve_o2m_operations(cr, uid, line_pool, line_ids, ["amount"], context)
 
         total = 0.0
         total_tax = 0.0
         for line in line_ids:
             line_amount = 0.0
-            line_amount = line[2] and line[2].get('amount',0.0) or 0.0
-            voucher_line_ids += [line[1]]
+            line_amount = line.get('amount',0.0)
             voucher_total += line_amount
 
         total = voucher_total
@@ -1008,4 +1012,22 @@ class account_bank_statement_line(osv.osv):
 
 account_bank_statement_line()
 
+def resolve_o2m_operations(cr, uid, target_osv, operations, fields, context):
+    results = []
+    for operation in operations:
+        result = None
+        if not isinstance(operation, (list, tuple)):
+            result = target_osv.read(cr, uid, operation, fields, context=context)
+        elif operation[0] == 0:
+            # may be necessary to check if all the fields are here and get the default values?
+            result = operation[2]
+        elif operation[0] == 1:
+            result = target_osv.read(cr, uid, operation[1], fields, context=context)
+            result.update(operation[2])
+        elif operation[0] == 4:
+            result = target_osv.read(cr, uid, operation[1], fields, context=context)
+        if result != None:
+            results.append(result)
+    return results
+
 # vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
diff --git a/addons/sale/sale.py b/addons/sale/sale.py
index d9acbe17089..dee4da8952e 100644
--- a/addons/sale/sale.py
+++ b/addons/sale/sale.py
@@ -1013,7 +1013,9 @@ class sale_order_line(osv.osv):
 
     def product_id_change(self, cr, uid, ids, pricelist, product, qty=0,
             uom=False, qty_uos=0, uos=False, name='', partner_id=False,
-            lang=False, update_tax=True, date_order=False, packaging=False, fiscal_position=False, flag=False):
+            lang=False, update_tax=True, date_order=False, packaging=False, fiscal_position=False, flag=False, context=None):
+        context = context or {}
+        lang = lang or ('lang' in context and context['lang'])
         if not  partner_id:
             raise osv.except_osv(_('No Customer Defined !'), _('You have to select a customer in the sales form !\nPlease set one customer before choosing a product.'))
         warning = {}
@@ -1146,7 +1148,9 @@ class sale_order_line(osv.osv):
 
     def product_uom_change(self, cursor, user, ids, pricelist, product, qty=0,
             uom=False, qty_uos=0, uos=False, name='', partner_id=False,
-            lang=False, update_tax=True, date_order=False):
+            lang=False, update_tax=True, date_order=False, context=None):
+        context = context or {}
+        lang = lang or ('lang' in context and context['lang'])
         res = self.product_id_change(cursor, user, ids, pricelist, product,
                 qty=qty, uom=uom, qty_uos=qty_uos, uos=uos, name=name,
                 partner_id=partner_id, lang=lang, update_tax=update_tax,
diff --git a/addons/sale/sale_view.xml b/addons/sale/sale_view.xml
index eb902e3058e..e61a810ae6a 100644
--- a/addons/sale/sale_view.xml
+++ b/addons/sale/sale_view.xml
@@ -128,21 +128,21 @@
                                             <field colspan="4"
                                                 context="{'partner_id':parent.partner_id, 'quantity':product_uom_qty, 'pricelist':parent.pricelist_id, 'shop':parent.shop_id, 'uom':product_uom}"
                                                 name="product_id"
-                                                on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], True, parent.date_order, product_packaging, parent.fiscal_position, False)"
+                                                on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, True, parent.date_order, product_packaging, parent.fiscal_position, False, context)"
                                                 />
                                             <field
                                                 context="{'partner_id':parent.partner_id, 'quantity':product_uom_qty, 'pricelist':parent.pricelist_id, 'shop':parent.shop_id, 'uom':product_uom}"
                                                 name="product_uom_qty"
-                                                on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], False, parent.date_order, product_packaging, parent.fiscal_position, True)"
+                                                on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, False, parent.date_order, product_packaging, parent.fiscal_position, True, context)"
                                                 />
                                             <field name="product_uom"
-                                                on_change="product_uom_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], False, parent.date_order)"/>
+                                                on_change="product_uom_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, False, parent.date_order, context)"/>
                                             <field groups="product.group_uos" name="product_uos_qty"/>
                                             <field groups="product.group_uos" name="product_uos"/>
                                             <field
                                                 name="product_packaging"
                                                 context="{'partner_id':parent.partner_id, 'quantity':product_uom_qty, 'pricelist':parent.pricelist_id, 'shop':parent.shop_id, 'uom':product_uom}"
-                                                on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], False, parent.date_order, product_packaging, parent.fiscal_position, False)"
+                                                on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, False, parent.date_order, product_packaging, parent.fiscal_position, False, context)"
                                                 domain="[('product_id','=',product_id)]"
                                                 groups="base.group_extended"/>
 
diff --git a/addons/sale_layout/sale_layout_view.xml b/addons/sale_layout/sale_layout_view.xml
index 6dee4ddd62f..dbea639f86e 100644
--- a/addons/sale_layout/sale_layout_view.xml
+++ b/addons/sale_layout/sale_layout_view.xml
@@ -22,23 +22,23 @@
                                             context="{'partner_id':parent.partner_id,'quantity':product_uom_qty,'pricelist':parent.pricelist_id,'shop':parent.shop_id,'uom':product_uom}"
                                             name="product_id"
                                             attrs="{'readonly':[('layout_type','!=','article')]}"
-                                            on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], True, parent.date_order, product_packaging, parent.fiscal_position)"
+                                            on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, True, parent.date_order, product_packaging, parent.fiscal_position, False, context)"
                                             select="1"/>
                                         <field
                                             context="{'partner_id':parent.partner_id,'quantity':product_uom_qty,'pricelist':parent.pricelist_id,'shop':parent.shop_id,'uom':product_uom}"
                                             name="product_uom_qty"
                                             attrs="{'readonly':[('layout_type','!=','article')]}"
-                                            on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], False, parent.date_order, product_packaging, parent.fiscal_position)"
+                                            on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, False, parent.date_order, product_packaging, parent.fiscal_position, False, context)"
                                             select="1"/>
                                         <field name="product_uom"
                                                required="0"
                                             attrs="{'readonly':[('layout_type','!=','article')],  'required':[('layout_type','not in',['title','text','subtotal','line','break'])]}"
-                                            on_change="product_uom_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], False, parent.date_order)"/>
+                                            on_change="product_uom_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, False, parent.date_order, context)"/>
                                         <field
                                             name="product_packaging"
                                             attrs="{'readonly':[('layout_type','!=','article')]}"
                                             context="{'partner_id':parent.partner_id,'quantity':product_uom_qty,'pricelist':parent.pricelist_id,'shop':parent.shop_id,'uom':product_uom}"
-                                            on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, 'lang' in context and context['lang'], False, parent.date_order, product_packaging, parent.fiscal_position)"
+                                            on_change="product_id_change(parent.pricelist_id,product_id,product_uom_qty,product_uom,product_uos_qty,product_uos,name,parent.partner_id, False, False, parent.date_order, product_packaging, parent.fiscal_position, False, context)"
                                             domain="[('product_id','=',product_id)]"
                                             groups="base.group_extended"/>
                                         <separator colspan="4" string="Manual Description" />