Thanks Tomasz, this resolved the issue for me. In my case, an ATI Radeon Mobility card X300 in a Thinkpad, an upgrade from Karmic to Lucid installed the nvidia-current package, and left a message in the Xorg log:
(EE) Failed to initialize GLX extension (Compatible NVIDIA X driver not found) ... uninstalling the package fixed it for me, got compiz back! -- [Lucid] KWin composite don't start in KDE 4.4 RC 1 https://bugs.launchpad.net/bugs/506623 You received this bug notification because you are a member of Ubuntu-X, which is subscribed to mesa in ubuntu. _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : [email protected] Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp

