gdm woes

[Jack Stalnaker <stalnaker tamu edu>]

Okay, I would like to do something seemingly simple with gdm that is a piece
of cake with plain jane xdm, but I cannot seem to manage it.  In a nutshell,
I would like to start my linux box and see on the screen the gdm chooser, so
that I can pick which computer (including my own) I would like to display on
my screen. With XDM, this was accomplished by commenting out all local 
servers in /etc/X11/xdm/Xservers and having /etc/inittab execute a shell
script on runlevel five that simply contained:

/path to xdm/xdm
exec X -indirect address.of.my.own.computer

thereby starting the xdm daemon without displaying it (all servers commented
out), and then sending an indirect XDMCP request to my own computer, bringing
up XDM's chooser. This is great, but I'd like to use gdm.  I've tried every
thing.  I edited gdm.conf to allow indirect and XDMCP requests, I've tried
commenting out the servers at the bottom of gdm.conf, I've tried the shell
script, all to no avail.  I just keep getting the same errors: 
X authentication errors left and right...I can't figure out how to make this
work. Any suggestions?

--Jack