Comment 12 for bug 425303

Great debugging there, marmuta. On my system I see this in the udevadm output:
udev_event_execute_rules: no node name set, will use kernel supplied name 'dri/card0'
while you get:
udev_event_execute_rules: no node name set, will use kernel supplied name 'card0'

I know the old Jaunty udev rules would add "dri/" explicitly.

This is something that has changed in the main kernel (and in the udev rules) but not yet in the drm-modules-source.