No login screen after boot or log out
After updating Fedora (using up2date), I no longer get a gui login screen when I boot the machine. The X symbol appears on the screen and it moves with the mouse, but then it disappears and nothing else happens.
<ctrl-alt-F1> gives me a text login prompt.
If I keep hitting some different <ctrl-alt-F#> keys, eventually the gui login screen appears. After that I can log in and everything works fine.
When I log out, I get the same blank screen and only a few well chosen <ctrl-alt-F#> keys will make the gui login screen reappear.
This may be an unrelated observation, but when I am logged in and everything seems happy, it appears that there are two X servers running:
localhost 77% ps waxf
PID TTY STAT TIME COMMAND
1 ? S 0:04 init 
2 ? SW 0:00 [keventd]
45 ? S 0:00 /usr/bin/X11/X -s off -dpms -v -nolock -fp /usr/lib/X11/fonts/misc -logfile /initrd/XFree86.0.log :0 vt8
6499 ? S 0:00 /usr/bin/gdm-binary -nodaemon
6540 ? S 0:00 \_ /usr/bin/gdm-binary -nodaemon
6541 ? S 0:28 \_ /usr/X11R6/bin/X :0 -audit 0 -auth /var/gdm/:0.Xauth -nolisten tcp vt7
6555 ? S 0:00 \_ -/bin/tcsh -c /usr/bin/ssh-agent /home/user/.Xclients
6600 ? S 0:00 \_ gnome-session
6601 ? S 0:00 \_ /usr/bin/ssh-agent /home/user/.Xclients