I am having the same problem, with MacBookPro8,2 and Apple Magic Mouse.
Use Lion? Just normal.
Open Windows 7 on Parallels 6? Just as perfect as in OSX.
Open Warcraft 3? Buggy mouse!
I don't really get this, please help!
[EDIT - 2012/may/28, 08h42]
I just discovered that if I move the mouse REALLY fast in any parallels window, I get the same buggy effect that I get inside the game - only difference is that in the game only a little fast is already enough to get the effect, while outside the game I need to move it way faster.
Is this a good tip for you to address this issue?
Last edited: May 28, 2012