diff --git a/addons/mass_mailing/wizard/test_mailing.py b/addons/mass_mailing/wizard/test_mailing.py
index 20c57f80609..ea570ebb755 100644
--- a/addons/mass_mailing/wizard/test_mailing.py
+++ b/addons/mass_mailing/wizard/test_mailing.py
@@ -11,7 +11,8 @@ class TestMassMailing(osv.TransientModel):
     _columns = {
         'email_to': fields.char('Recipients', required=True,
             help='Comma-separated list of email addresses.'),
-        'mass_mailing_id': fields.many2one('mail.mass_mailing', 'Mailing', required=True),
+        'mass_mailing_id': fields.many2one(
+            'mail.mass_mailing', 'Mailing', required=True, ondelete='cascade'),
     }
 
     _defaults = {