You can install
Compiz Fusion Icon. I don't know if there's any "nice" place to get it for Ubuntu-users, but check those links:
http://tombuntu.com/index.php/2007/0...ion-tray-icon/
http://wiki.opencompositing.org/CompizFusionIcon
Otherwise you can use the flag
--indirect-rendering and perhaps some more flag when you start compiz. Please refer to the manual (
man compiz) for more info. I'm sorry I can't remember exacly how I did it (since I later started to use the C-F Icon, and then finally stopped using C-F).