I saw this on GFaqs 
1. No leaving the normal boundaries of a Map.
2. No going into the tunnel walls on Pipepline.
3. No going on top of the arch on District.
4. No going onto Invisible Ledges.
5. No jumping off of another Character.
6. No using the Grenade Launcher.
7. No using the Frag x 3 Perk.
8. No using C4.
9. No using Claymores.
10. No removing players on the opposing Team from the Private Match once a Game has started.
11. Breaking any of rules #1-10 will result in a Forfeit of the Game.
http://gamebattles.com/xbox360/call-of-duty-4/ladder/2008-mlg-pro-circuit-2/rules
6-9 :lol