I've had my mac for about one month now. In that time, I've seen the two buttons responsible for Dashboard and Expose on the mouse reset themselves to "Button 3" and "Button 4" several times. It just happened again today, two days after a full reformat to install Leopard. I can't seem to figure out why the buttons are resetting themselves. Does anyone have any ideas? The only thing I can think of is that I have a second mouse plugged in as well for when I play WoW. Perhaps that's confusing the OS?