Scrollbox behavio - a mind of its own?

[clr]

I have a new t61 6465cto with the preinstalled xp. Twice now, after running for a while, the scroll boxes will behave badly: if you put the cursor over the scrollbox, it will move to the far right bottom of the "page" and using the scroll bars to make it get positioned does not work. SOmetimes, you can use the arrow keys. Only solution is to reboot and wait until it happens again.

I know it is minor, but also very annoying and perhaps a sign of other problems..

Any help appreciated.