django-guardian 1.1.1 documentation
New in version 1.1.
Django 1.5 comes with the ability to customize default auth.User model - either by subclassing AbstractUser or defining very own class. This can be very powerful, it must be done with caution, though. Basically, if we subclass AbstractUser or define many-to-many relation with auth.Group (and give reverse relate name groups) we should be fine.
Important
django-guardian relies heavily on the auth.User model. Specifically it was build from the ground-up with relation beteen auth.User and auth.Group models. Retaining this relation is crucial for guardian - without many to many User (custom or default) and auth.Group relation django-guardian will BREAK.
See also
Read more about customizing User model introduced in Django 1.5 here: https://docs.djangoproject.com/en/1.5/topics/auth/customizing/#substituting-a-custom-user-model.