Do you have the problem if you use the official feisty package? The patch you pointed is part of the package so your description doesn't really makes sense. Are you sure you don't have a binary driver package install for nvidia or fglrx even if you don't use it?
-- 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
