Comment 3 for bug 626527

Here's a cause/workaround:

There is a discussion of this problem here: http://ubuntuforums.org/showthread.php?t=1383356&page=2
From post 15 by v_2ryann :

Here is the answer guys, on how to do it without changing the effects:

1) Open a terminal o press ALT+F2, then run/type: gconf-editor
2) Go to /desktop/gnome/remote_access and enable "disable_xdamage"

I found it found here:
http://swiss.ubuntuforums.org/showthread.php?t=1496368