Thank you for your bug. Do you use the nvidia binary drivers which divert mesa? The bug you pointed has been fixed to mesa already
** Changed in: mesa (Ubuntu) Importance: Undecided => Medium Status: Unconfirmed => Needs Info -- feisty: Assertion `c->xlib.lock' failed for all gl apps https://launchpad.net/bugs/88708 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs