Thanks for this consise and well-written brief.

This is great - thank you !

I spent ages looking fir how to do this! Good work.

Thanks for sharing this hard to find tip!

thanks, its working)

That is fantastic, no one would think it can be so simple.

thanks bro. short and sweet. wicked awesome.

excellent. I edited the /etc/gdm/gdm.conf with midnight commander. Changed the gdm.conf under xdmcp as listed above and all I had to do was restart the computer

Thank you very much!
connected to remote X server successful.

I've tried this but still can't pull up the desktop using Exceed XDMCP Query. When I put the IP address of the Ubuntu machine into the Exceed XDMCD Query window and hit "OK", the window goes away, then comes right back. This has worked fine on previous versions of Ubuntu, but can't seem to connect to the new Ibex.
Thanks for any help anyone can give!
Ternion

Ok, just to update everyone here:
I finally got it working. Had to manually change some settings in the gdm.conf file as follows:
* Uncomment and edit line in the [xdmcp] section to read "Enable=true"
* In System -> Administration -> LoginWindow
-- @ Remote tab
Change style to "Plain face with browser"
-- @ Security tab
Deselect "Deny TCP connections..."

Then rebooted and could finally pull up the Ubuntu Intrepid Ibex desktop from my XP machine using Exceed.
Hopefully this will help someone else with a similar problem.

thanks, Ternion

Thanks, saved my life man.

I had this working, then I made the mistake of updating to ubuntu 9.10. Now XDMCP doesn't work and the Login Window (as presented by gdmsetup doesn't HAVE a "Remote" tab! Further, the new version of GDM doesn't seem to use a gdm.conf (I think it's now custom.conf) and by defualt, the entire XDMCP section is absent!

Its really helpful.. i was searhing this solution for more that 48hrs finally got it.. please keep posting these kind of updates or solutions.. God bless u..:-)