How Do I set up a LAN (halo Custom Edition) game between 2 computers i have?



Hi, I have been having trouble trying to setup a LAN game. I have Halo Custom Edition on both om my computers, both of which have different cd keys, not the same one (my copies are authentic) and i cant work out how to have a 2 player LAN game with my friends. also if it matters, both computers have xp home edition, both very capible of playing halo. also, one computer is directly plugged in2 the modem and the other is on wireless internet (the modem has wireless capabilites). Please help if you know how to solve this problem. cheers, terminator95:)