I found out that when trying to activate your admin 'module' in my settings.py / INSTALLED_APPS, starting the embedded server will fail.
It turned out that one of the import statements referenced the wrong module for importing the LOOKUP_SEP constant.
from django.db.models.sql.constants import LOOKUP_SEP, QUERY_TERMS
from django.db.models.constants import LOOKUP_SEP
from django.db.models.sql.constants import QUERY_TERMS
made it actually compile and load so far.
What version of django are you running?
sorry for the late reply, but it is 1.5+
It works in latest version of Django. Closing issue.