Multiplayer Help

[soccerbuff86]

I want to set up an private multiplayer game for my friend and i. He has a mac and I have a pc (which shouldnt make a difference, right?) and we live in the same area. I have heard about lan but dont know how to set it up. Oh, we might also have different versions of the game, mine is from when it was first released and his is from the recent mac realease. Any help u could give me would be great. Just a basic overview of how to set it up, whether by lan or the internet, would be awesome. Thanx in advance.