diff --git a/gnuviechadmin/managemails/tests/test_models.py b/gnuviechadmin/managemails/tests/test_models.py
index a731ae0..4df1793 100644
--- a/gnuviechadmin/managemails/tests/test_models.py
+++ b/gnuviechadmin/managemails/tests/test_models.py
@@ -1,14 +1,22 @@
 from django.test import TestCase
+from django.test.utils import override_settings
+
 from passlib.hash import sha512_crypt
 
 from domains.models import MailDomain
 from osusers.models import User
+
 from managemails.models import (
     MailAddress,
     Mailbox,
 )
 
 
+@override_settings(
+    CELERY_ALWAYS_EAGER=True,
+    CELERY_CACHE_BACKEND='memory',
+    BROKER_BACKEND='memory'
+)
 class MailboxTest(TestCase):
     def test_set_password(self):
         user = User.objects.create_user()
@@ -16,6 +24,12 @@ class MailboxTest(TestCase):
         mb.set_password('test')
         self.assertTrue(sha512_crypt.verify('test', mb.password))
 
+    def test___str__(self):
+        user = User.objects.create_user()
+        mb = Mailbox.objects.create(username='test', osuser=user)
+        mb.set_password('test')
+        self.assertEqual(str(mb), 'test')
+
 
 class MailAddressTest(TestCase):
     def test__str__(self):