In Desperate Need Of Help With Xbox 360 System Link

Me and my friend have been trying to have a system link match of Gears of War for well over an hour now.

It can detect the system, as it wouldn't let us create a match otherwise, but it when the other person searches for the match it doesn't come up.  Can anyone help?  Any help would be much appreciated.

BUMP

Sorry, really need help with this

what's cat5? sorry, i know, i'm a noob lol

Okay, here's the setup;

My 360 on computer desk plugged into monitor, friend's 360 plugged into television on table.

The cable is plugged into both 360s.

And yeah, they've both been updated.  We put his 360 online dead quick to update it and still nothing happened.