diff --git a/gnuviechadmin/osusers/models.py b/gnuviechadmin/osusers/models.py
index c513574..ef1287a 100644
--- a/gnuviechadmin/osusers/models.py
+++ b/gnuviechadmin/osusers/models.py
@@ -57,7 +57,7 @@ class Group(TimeStampedModel, models.Model):
         return self
 
     def delete(self, *args, **kwargs):
-        delete_ldap_group_if_empty.delay(self)
+        delete_ldap_group_if_empty.delay(self.groupname)
         super(Group, self).delete(*args, **kwargs)
 
 
@@ -138,7 +138,7 @@ class User(TimeStampedModel, models.Model):
         ]:
             remove_ldap_user_from_group.delay(self.username, group.groupname)
         delete_ldap_user.delay(self)
-        delete_ldap_group_if_empty.delay(self.group)
+        delete_ldap_group_if_empty.delay(self.group.groupname)
         self.group.delete()
         super(User, self).delete(*args, **kwargs)
 
diff --git a/gnuviechadmin/osusers/tasks.py b/gnuviechadmin/osusers/tasks.py
index 5eff249..2cf9349 100644
--- a/gnuviechadmin/osusers/tasks.py
+++ b/gnuviechadmin/osusers/tasks.py
@@ -39,5 +39,5 @@ def delete_ldap_user(user):
 
 
 @shared_task
-def delete_ldap_group_if_empty(group):
+def delete_ldap_group_if_empty(groupname):
     pass