GDM on external notebook Display (opensuse 11.1)

Hi,
i have a dell latitude 630 notebook with NVIDIA graphics card and external display via docking station.

w/o external display connected, gdm should use the internal,
when docked in, gdm should use the external display.

this scenario worked fine in opensuse 10.3 and 11.0,
but since 11.1 gdm always starts on the internal monitor.

in BIOS setup, external display is primary when connected.

bootsplash is on external display, but not gdm.

what is wrong?