haven't a clue, but it reminds me of my sticky mouse problem.
I have a touchpad, and sometimes it sticks on one place in the screen like rubber. I can move it, but when i let go the pad, it springs back where it came from.
Also when i click something while it's acting up. like a menu, the menu appears only to instantly disappear, so i have to logout (or shutdown), using the keyboard, and login again to get it working.
The odd think about this is that it happened in windows ME and also in windows 98... but it also happens in kfm, Sawfish, and Enlightenment sometimes!
So it's a hardware problem, if it happens so much across the board? no! because if it were, it would persist when i restart, but a restart usually fixes it, if not, another restart hot on the heels of the first one always does.
I can't help you with the problem btw but just thought i'd share my own weird stuff experiences so you know yr not alone!