XBox Live cannot connect to party on Airport Express

[actingbiz1]

I have been scouring google for hours to this solution and cannot find a solution.
I have an Airport Express acting as the router, connected to the ethernet jack in my dorm.
Now, my NAT is OPEN.
But I cannot connect to my friends online.

DOES ANYONE have a working configuration????

 

[uv23]

This may help you: http://xbox.joystiq.com/2007/02/26/xbox-360-and-airport-extreme-compatibility-fix/

I had to switch to b/g instead of n to get my 360 working with my airport extreme.