[C/P]
All u need to do, to enable loopback for your router. If your router doesnt have this function. Then you'll' have to manually hack into your router if your router is linux based. As far as i know, some dlink or linksys are linux based.
1st, you'll need to register a dynamic dns from
www.dyndns.com. Don't worry, its free. For example this is the domain ur registered ====> portforward.dyndns.org. And 192.168.0.2 is the computer which is hosting the game.
2nd, your need to Putty (google it yourself) or any supported telnet clients. Login in as root. cd into /etc then type this into your telnet client.
echo 192.168.0.2 portforward.dyndns.org >> hosts
3rd. For the other computers. Set your tcp/ip settings. If your router's ip is 192.168.0.1 then u shud enter 192.168.0.1 for dns ip.
There you go, your done. Enjoy ur game. Work wonderfully for me.
The router i used is a modded old computer turned into linux router called ipcop. =D