This bug should have component=gdm, but no such component is available at the time I enter this bug. On an Intel system running RHL 6.0 (upgraded from 5.2 despite the problems with a hard disk install), I had both xdm and gdm installed. I chose to remove gdm with "rpm -e gdm". After that the file /etc/X11/prefdm still pointed to, the now missing, gdm rather than to xdm. The result is no X.
Ooops. It should go away on reboot; we'll start looking at in place solutions.
This issue has been forwarded to a developer for further action.
will be fixed in initscripts in the next rawhide release.