You see, maybe if you think of the event as not only a conference, that might be evaluated by how many PhDs are going, or only held by a computer department in a University, you might have more shots.
The event has many features, it can be seen as an art festival on new media and technology, it has the free software appeal to it too.
I just say that because in Sao Paulo we didn't have a music department from an Univesrity behind it (the link to the University was Digital Desing), and we got a lot of support mainly for being an "art festival", like, one main supporter was the Museum of Image and Sound.
So maybe there are much more options in Germany if you look for collaborations between cities, and national institutions that support this kind of thing/festival - I have no idea how it works there so I may just shut up already, I think you got my point...
cheers