I have a django table auth_user and for some reason some of the access codes are stored like sha1$... others pbkdf2_sha256$... . I don't see any rhymes or reasons for this - what is the difference between the two and why would some be kept as one version and others as others?
auth_user
sha1$...
pbkdf2_sha256$...
Perhaps you have upgraded from Django 1.3 to Django 1.4 keeping user data intact? Django 1.4 introduced a new, more secure hash for storing passwords, but should still be backward compatible with older hashes as far as I know.