diff --git a/modoboa/core/migrations/0004_auto_20150728_1228.py b/modoboa/core/migrations/0004_auto_20150728_1228.py
index cee67bfe9..a7fa76773 100644
--- a/modoboa/core/migrations/0004_auto_20150728_1228.py
+++ b/modoboa/core/migrations/0004_auto_20150728_1228.py
@@ -2,6 +2,7 @@ from django.db import models, migrations
 
 
 class Migration(migrations.Migration):
+
     dependencies = [
         ("core", "0003_user_master_user"),
     ]
@@ -41,11 +42,8 @@ class Migration(migrations.Migration):
             ),
             preserve_default=True,
         ),
-        migrations.AddConstraint(
-            model_name="user",
-            constraint=models.UniqueConstraint(
-                fields=("email", "is_active"),
-                name="core_user_email_c0c03f_idx",
-            ),
+        migrations.AlterIndexTogether(
+            name="user",
+            index_together=set([("email", "is_active")]),
         ),
     ]