255: Cannot type, keyboard gets ignored

Hi,

I've got build 255 on VS2003. It sometimes happens that I cannot use the
keyboard anymore. When I press a key, nothing happens. But the mouse
still works fine, I can click menus, select text and everything else..
just the key presses get lost. To get the keyboard working again, I have
to restart VS. This happened 4 times today.

I have noticed that when I press Alt-Tab I see some "unknown" window in
the program list. That window disappears when I close VS. Not sure if
that has something to do with it.. I haven't noticed it in earlier
versions though.

Any ideas?

thanks,
Max