bitmazk/django-registration-email — pull request #27 by maurodec (2013-11-26 13:06:42+00:00)
Title: Allow using a custom User model via the get_user_model function.

This should fix Issue #24.

Note that this has not been fixed in django-registration and the repo owner seems to be rejecting pull requests. There are however forks like [this](https://bitbucket.org/Lilas/django-registration-1.5) one that fix the problem, so I suggest using them instead of vanilla django-registration.