Comment 2 for bug 892475

The server error is gone, now an error message is shown in the form (e.g. username: 'test_accents_é_è'):

"Enter a valid username. This value may contain only letters, numbers and @/./+/-/_ characters."

This is an error from Django, because it does not use utf8 encoding as default for usernames. This will be fixed in Django 1.10. when using python3. When using python2 and Django 1.10 default will ever be ASCII, but with the option for unicode. See the box in:

https://docs.djangoproject.com/en/1.10/ref/contrib/auth/#django.contrib.auth.models.User.username

The current behavior with the provided error message is not the best, but better then the old behavior (server error). Is this Error message helpful?