Solving (partially) South issue on not updating permissions.
9 Mar
South have a already know issue [1] about no update permissions of added models. The common fix is run manage.py syncdb –all, Django Extensions [2] app also have a management command called update_permissions what is very usefull and also do the job.
But, any of us want to remember about that every time, so to automatize permissions creation I ‘copied’ idea of Django Extensions update_permissions command and put it to a method connect to a post_migrate [3] South signal. This do the job every time a app is migrated and with time can be extended to remove permissions also 
. The code use built in Django features.
Here is the code, I put it in my project/__init__.py:
Links:
[1] http://south.aeracode.org/ticket/211
[2] http://packages.python.org/django-extensions/
[3] http://south.aeracode.org/docs/signals.html#post-migrate
I change the line 10
import settings
For
from django.conf import settings
For django work in evolution of settings.