X only starts with Ethernet cable plugged in

[Dave Martini]

I have a RHEL 5.2 machine.
My /etc/inittab has this line

id:5:initdefault:

However, when the network cable is unplugged, I just get a 
text login prompt and no X11. 

If I type 

# startx

I get errors saying the server is already active for display 0

As soon as I plug the ethernet cable into the machine, X11 starts up
and I'm presented with the graphical login window.

Does anyone have any ideas why this is the case?

This is a laptop system and I will not have network connectivity all the time
but still need to log into it with a local account and expect X11 to work.

Thanks.
Dave Martini
LLNL