I've never even heard of that type of behavior... there are a few things you could try, I suppose.
The first would be to use Disk Utility (Applications>Utilities folder) and use it to verify and repair permissions. Also, just for the heck of it, verify your hard drive while you're there (you won't be able to repair it if errors are shown). If errors do come up, you'll have to boot to your Recovery partition (holding down the Command and R keys whilst booting) and use Disk Utility there to repair your hard drive.
If a repair of your permissions doesn't solve the problem and there are no errors on your hard drive, I would recommend just installing the OS again. Boot to your Recovery partition and elect to install a 'fresh' copy of ML. It wont' hurt any of your data, apps, etc., but it might get rid of the 'sticky' cursor problem.