Thanks for answering so fast. I didn't see this anywhere, but I didn't understand how it is supposed to work after reading http://www.djangoproject.com/documentation/db_api/#many-to-one-relations (just behind the one-to-one part, but obviously not working in a similar way), and I don't understand yet the name mangling, the assumptions about fields etc. which Django does; being a Django newbie (with some Python programming experience), this still looks like Voodoo to me.
Tobias
