Since all of the xorg releases that are now in portage make /usr/X11R6/ obsolete and use generic /usr/ {bin,lib...} gdm.config should probably be corrected to use the bins: /usr/bin/X and /usr/bin/Xnest instead of: /usr/X11R6/bin/X and /usr/X11R6/bin/Xnest
Created attachment 71469 [details] fixed gdm.conf This is gdm.conf with fixed path of X binaries pointing to /usr/ rather than /usr/X11R6/
Fixed in CVS.