Seperate active video memory for each MacOSX user

Right now the multiple users feature in MacOSX 10.3 allows background users to continue their work, even playing sound while in the background. Unfortunately, in contrast to Windows XP a background user on MacOSX has no active video. If you run a VNC server on MacOSX and switch another user to the foreground, the VNC connection is lost, as there is no more active video for a background user. So when I am away from my Mac somewhere in the world and access my Mac at home via VNC, when my girl friend at home activates her Mac user, my VNC connection is interrupted.