diff --git a/openerp/addons/base/ir/ir_actions.py b/openerp/addons/base/ir/ir_actions.py
index 0b60d389287..67c36b277dd 100644
--- a/openerp/addons/base/ir/ir_actions.py
+++ b/openerp/addons/base/ir/ir_actions.py
@@ -936,10 +936,9 @@ class act_client(osv.osv):
             for record in self.browse(cr, uid, ids, context=context)
         ])
 
-    def _set_params(self, cr, uid, ids, field_name, field_value, arg, context):
+    def _set_params(self, cr, uid, id, field_name, field_value, arg, context):
         assert isinstance(field_value, dict), "params can only be dictionaries"
-        for record in self.browse(cr, uid, ids, context=context):
-            record.write({field_name: repr(field_value)})
+        self.write(cr, uid, id, {'params_store': repr(field_value)}, context=context)
 
     _columns = {
         'tag': fields.char('Client action tag', size=64, required=True,
diff --git a/openerp/osv/fields.py b/openerp/osv/fields.py
index 782cc8e796a..fb973d2e521 100644
--- a/openerp/osv/fields.py
+++ b/openerp/osv/fields.py
@@ -852,12 +852,13 @@ class function(_column):
     This callable implements the write operation for the function field
     and must have the following signature:
 
-    .. function:: fnct_inv(model, cr, uid, ids, field_name, field_value, fnct_inv_arg, context)
+    .. function:: fnct_inv(model, cr, uid, id, field_name, field_value, fnct_inv_arg, context)
 
         Callable that implements the ``write`` operation for the function field.
 
         :param orm_template model: model to which the field belongs (should be ``self`` for
                                    a model method)
+        :param int id: the identifier of the object to write on
         :param str field_name: name of the field to set
         :param fnct_inv_arg: arbitrary value passed when declaring the function field
         :return: True