xrandr does not find modes defined in xorg.conf

[Nils]

Thanks! Adding

Option          "MetaModes"     "1024x768-1024x768 1024x768 800x600 640x480"

in the "Device" section fixed the problem first, however I don't know
what it does.. Also ctrl-alt-+/- does still not work. I also noticed
that you can choose the res now correct in kcontrol.

Nils