Comment 57 for bug 283128

The https://bugs.launchpad.net/ubuntu/+source/xkeyboard-config/+bug/283128/comments/52 patch is working all right (although it is impossible to push it to the upstream). You may fetch the patched xserver package from http://repo.paulus.ru/karmic/ (you need the xserver-xorg-core package) or build one yourself.