Hey, I love this app. However, just spent 2 days to diagnose it as the culprit in causing my tests with geoDjango to fail (on PostGIS, they worked well in MySQL oddly enough). It's the wierdest thing because the unit tests would error out AFTER tearDown, but BEFORE setUp.
I posted my errors here: http://stackoverflow.com/questions/2246698/getting-internalerror-no-such-savepoint-with-postgis-in-django-even-when-using and then answered it saying I found the cause to be this app (though no idea what particularly in the app is causing it... something to do with the content-type, and authentication stuff).
I'll update you again if I find out more, or maybe even send up a patch so that others won't come across this same problem in the future. I'll track this bug, so update it with any notes, suggestions, updates, or just let me know what other info I can provide to be helpful.
Keep up the good work, and let's fix this.