GTA IV/Games for Windows Live Connection Problem

Hi all,

Now that GTA IV can be had for under $20, a bunch of buddies of mine went out and bought copies of it. We tried to play a multiplayer game last night, and everthing went smoothly except for one thing: Two of my friends, we'll call them Friend #1 and Friend #2, they could each connect to the server independantly of each other, but if Friend #1 was already in the server, Friend #2 would boot them off, and vice versa.

All firewalls and security software was shut off to test for problems, and it didn't help. All copies of the game were legit, so no possibility of having the same key code or anything. Friends were in two different parts of the city, so no chance of having the same IP address.

Does anyone know what would cause this? Could it be something to do with Games for Windows Live?

Gryphyn