FC5 - auto-login not working?

[B Wooster]

On my FC5 VMWare box, I'm trying to set it up to autologin on a user
account called "cgi".

This user exists, I can manually log in.

But when I go to the "Login Screen" administation tool, on the
"Security" tab, when I check-mark  "Enable Auto-Login" and go to
select the user, there is no user in the pull-down text field - it is
all blank. I can type in the word "cgi" in here, but this is lost next
time I go into Login Screen, and I also tried rebooting, and it does
not auto-login.

Which system config files are used to enable auto-login? Maybe I can
manually set this up, and not use gdmsetup.