After a wipe and re-install, I've not encountered this again. Funnily enough in hindsight, it acts in a similar manner as if there was some kind of permission mismatch; but I can't go back and verify it now.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-control-center in Ubuntu. https://bugs.launchpad.net/bugs/908592 Title: System Settings > Keyboard Layout Options > Key Sequence To Kill the X Server setting not persistent Status in “gnome-control-center” package in Ubuntu: New Bug description: Ubuntu 11.10 Via System Settings > Keyboard Layout > Options, enable CTRL+ALT+BACKSPACE to kill X server. Close System Settings Open System Settings > Keyboard Layout > Options Note value is no longer checked. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/908592/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp

