As per the upstream bug report and my last few comments, this was pinpointed to a bug in metacity rather than X.
I think it may be resolved in metacity, as well, since it's been a long time since I saw this. ** Changed in: xorg-server (Ubuntu) Status: Triaged => Invalid -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/654768 Title: compositor produces artefacts starting in maverick To manage notifications about this bug go to: https://bugs.launchpad.net/xorg-server/+bug/654768/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp