After login, the command

	xauth list

prints only

loki/unix:0  MIT-MAGIC-COOKIE-1
			203b164a0376210828697c55024a003d

i.e., authority is only being set for Unix domain sockets.
It should also create an entry for AF_INET domain sockets,
so applications running on a remote machine can display
locally.  In other words, there should also be an entry
that looks like

loki:0  MIT-MAGIC-COOKIE-1  203b164a0376210828697c55024a003d

The the Xauthority can be set on a remote machine in the
standard way:
loki:0  MIT-MAGIC-COOKIE-1  203b164a0376210828697c55024a003d
	xauth extract loki:0 - | rsh remote xauth merge -

and the display variable set

	export DISPLAY=loki:0

on the remote machine, and X applications can be started.

Both xdm and kdm work properly; gdm represents a step
backwords in this respect.

The easy fix is to use kdm or xdm instead of gdm; simply

	cd /etc/X11
	rm prefdm
	ln -s ../../usr/bin/kdm prefdm