diff --git a/addons/portal_sale/portal_sale.py b/addons/portal_sale/portal_sale.py
index aef730ab0a2..b79be7391e1 100644
--- a/addons/portal_sale/portal_sale.py
+++ b/addons/portal_sale/portal_sale.py
@@ -126,7 +126,7 @@ class account_invoice(osv.Model):
 class mail_mail(osv.osv):
     _inherit = 'mail.mail'
 
-    def _postprocess_sent_message(self, cr, uid, mail, context=None):
+    def _postprocess_sent_message(self, cr, uid, mail, context=None, mail_sent=True):
         if mail.model == 'sale.order':
             so_obj = self.pool.get('sale.order')
             order = so_obj.browse(cr, uid, mail.res_id, context=context)
@@ -138,4 +138,4 @@ class mail_mail(osv.osv):
             for p in mail.partner_ids:
                 if p.id not in order.message_follower_ids:
                     so_obj.message_subscribe(cr, uid, [mail.res_id], [p.id], context=context)
-        return super(mail_mail, self)._postprocess_sent_message(cr, uid, mail=mail, context=context)
+        return super(mail_mail, self)._postprocess_sent_message(cr, uid, mail=mail, context=context, mail_sent=mail_sent)
diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index b47320b1e79..c4e276d943e 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -1254,10 +1254,10 @@ class mail_mail(osv.Model):
     _name = 'mail.mail'
     _inherit = 'mail.mail'
 
-    def _postprocess_sent_message(self, cr, uid, mail, context=None):
+    def _postprocess_sent_message(self, cr, uid, mail, context=None, mail_sent=True):
         if mail.model == 'purchase.order':
             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)
+        return super(mail_mail, self)._postprocess_sent_message(cr, uid, mail=mail, context=context, mail_sent=mail_sent)
 
 
 class product_template(osv.Model):