Dvorak on Ubuntu (after something goes wrong)

Update: You probably won't run into any of the troubles below. See for how to set up Dvorak on Ubuntu in the first place.

Setting Dvorak as the default keyboard worked out of the box in Ubuntu. Someone else used the virtual machine and changed things and it broke now.

Currently, only way to change is:

setxkbmap dvorak

Using the system preferences user interface for keyboard settings does nothing and triggers this error in the background:

Error activating XKB configuration.
It can happen under various circumstances:
- a bug in libxklavier library
- a bug in X server (xkbcomp, xmodmap utilities)
- X server with incompatible libxkbfile implementation

X server version data:
The X.Org Foundation
10604000

If you report this situation as a bug, please include:
- The result of xprop -root | grep XKB
- The result of gconftool-2 -R /desktop/gnome/peripherals/keyboard/kbd

Reference

http://ubuntu-tutorials.com/2008/01/31/changing-the-system-keyboard-mapping-on-ubuntu-dvorak-vs-qwerty/