alex/django-filter — pull request #80 by mammique (2013-03-07 20:00:53+00:00)
Title: Add support for non-symmetrical m2m fields

Django-filter raises and exception on ManyToManyField that has the symmetrical option set to False. Here is a patch that fixed it for my case (sounds logical to me, but I'm not an expert on Django's ORM).

Camille.