I just discovered that this was my problem as well though I am using amd64 and lucid. When cgroup-bin is installed all operations involving adding or removing modules fail (modprobe, rmmod). There may be other factors at play but for my system once installing cgroup-bin I can reproduce 100% of the time by running "sudo modprobe aes". Removing the packages fixes the problem.
** Changed in: libcgroup (Ubuntu) Status: New => Confirmed -- gnome locks up with cgroup-bin installed https://bugs.launchpad.net/bugs/598335 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs