It's a known django issue if you create your models, run syncdb
and then add a ManyToManyField
on one of your models. In this situation running syncdb
again wouldn't help - it wouldn't pick and apply your model changes, see:
The best way to go is to start using South - it can track your model changes and apply them through the schema and data migrations mechanism. It's worth trying.
Just FYI, you can also create that necessary many-to-many table manually.
Hope that helps.