One regular account can't login via gdm

[Sune Mølgaard]

Hi all.

Not sure if this is the right list, but I'll try.

My own account can login just fine, but my girlfriend's can't. 
.xsession-errors states the following:

/etc/gdm/PreSession/Default: Registering your session with wtmp and utmp
/etc/gdm/PreSession/Default: running: /usr/bin/sessreg -a -w 
/var/log/wtmp -u /var/run/utmp -x "/var/lib/gdm/:0.Xservers" -h "" -l 
":0" "michelle"
/etc/gdm/Xsession: Beginning session setup...
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified

Couldn't connect to X server.
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified

I notice, that her .Xauthority is empty. Might that be the cause, and 
how do I generate a real one for her?

Best regards,

Sune Mølgaard