I just got a usb optical intellimouse. I'm assuming I continue to use the IMPS/2 like I have been with my current standard intellimouse. But I can't seem to get the roller wheel working. I have the Option "ZAxisMapping" "4 5" set correctly.. If I put my regular intellipoint mouse on it everything is peachy, but when I switch and restart x the wheel just won't spin!!! Any ideas? faulty mouse? Thanks.