pennersr/django-allauth — pull request #148 by m-thielen (2012-11-29 12:06:16+00:00)
Title: Raise exception if import of provider urls module fails because of external dependency

In my case, httplib2 was missing, causing the import of the facebook provider urls module to fail. The error I got was a "no reverse match" error, which was rather hard to trace down.

There might be (probably are ;-) ) smarter ways to handle this situation, but this works for me.