Are you trying to play through a hub? You didn't give us too much information. If you are using a hub and have a few computers on a network using a hub, you must set up an IP for each computer in Windows. Once this is done on each of the computers you need to select start LAN game in MOH and once you've got your server running, each of the other computers be able to see the server when they call up a list.
Hope this helps...