diff --git a/addons/account/account.py b/addons/account/account.py
index 655db7065d5..c08be3323b5 100644
--- a/addons/account/account.py
+++ b/addons/account/account.py
@@ -1655,26 +1655,6 @@ class account_move_reconcile(osv.osv):
                                                         opening/closing fiscal year process.'))
         return super(account_move_reconcile, self).unlink(cr, uid, ids, context=context)
     
-    # Look in the line_id and line_partial_ids to ensure the partner is the same or empty
-    # on all lines. We allow that only for opening/closing period
-    def _check_same_partner(self, cr, uid, ids, context=None):
-        for reconcile in self.browse(cr, uid, ids, context=context):
-            move_lines = []
-            if not reconcile.opening_reconciliation:
-                if reconcile.line_id:
-                    first_partner = reconcile.line_id[0].partner_id.id
-                    move_lines = reconcile.line_id
-                elif reconcile.line_partial_ids:
-                    first_partner = reconcile.line_partial_ids[0].partner_id.id
-                    move_lines = reconcile.line_partial_ids
-                if any([(line.account_id.type in ('receivable', 'payable') and line.partner_id.id != first_partner) for line in move_lines]):
-                    return False
-        return True
-
-    _constraints = [
-        (_check_same_partner, 'You can only reconcile journal items with the same partner.', ['line_id', 'line_partial_ids']),
-    ]
-    
     def reconcile_partial_check(self, cr, uid, ids, type='auto', context=None):
         total = 0.0
         for rec in self.browse(cr, uid, ids, context=context):
diff --git a/addons/account/account_move_line.py b/addons/account/account_move_line.py
index 982b1d8c23b..d38b604cb15 100644
--- a/addons/account/account_move_line.py
+++ b/addons/account/account_move_line.py
@@ -22,7 +22,7 @@
 import time
 from datetime import datetime
 
-from openerp import workflow
+from openerp import api, workflow
 from openerp.osv import fields, osv
 from openerp.tools.translate import _
 import openerp.addons.decimal_precision as dp
@@ -607,6 +607,27 @@ class account_move_line(osv.osv):
             cr.execute('CREATE INDEX account_move_line_date_id_index ON account_move_line (date DESC, id desc)')
         return res
 
+    @api.constrains('reconcile_id', 'reconcile_partial_id')
+    def _check_reconcile_same_partner(self):
+        """ Ensure the partner is the same or empty on all lines and a reconcile mark.
+            We allow that only for opening/closing period"""
+        for line in self:
+            rec = False
+            move_lines = []
+            if line.reconcile_id:
+                rec = line.reconcile_id
+                move_lines = rec.line_id
+            elif line.reconcile_partial_id:
+                rec = line.reconcile_partial_id
+                move_lines = rec.line_partial_ids
+            if rec and not rec.opening_reconciliation:
+                first_partner = line.partner_id
+                for rline in move_lines:
+                    if (rline.partner_id != first_partner and
+                            rline.account_id.type in ('receivable', 'payable')):
+                        raise osv.except_osv(
+                                _('Error!'), _("You can only reconcile journal items with the same partner."))
+
     def _check_no_view(self, cr, uid, ids, context=None):
         lines = self.browse(cr, uid, ids, context=context)
         for l in lines: