Cannot record/send automation!

[MasterFusion]

Hey guys...I have a problem with my Virus B and Cubase 4: When I'm moving a knob, Cubase doesn't record the movement. Also, when I draw a line on my own on the CC parameter, the Virus doesn't seem to receive the data!
I've tried and checked everything that came into my mind. In Virus settings, "Midi Panel" is set to "Int + Midi", global channel/deviceID etc. is all set up correctly. I've tried it with a vst intrument-track and a midi-track + audio-track, both don't do it.
The strange thing is, apart from this automation thing, the Virus is integrated in Cubase well...so the notes I play are being send to the Virus, and the audio is getting back to Cubase..recording audio is no problem either. Also, the SoundDiver works without problems, I can send and receive sounds with it, so the midi setup should work.
Any ideas what else I could check? I'd be glad for any advice, since I need to get this to work asap ..