To use a command line to initiate a multiplayer session that you are hosting, click Start, click Run, and then type the following in the Open box (or at the MS-DOS prompt):
monster.exe /h
To use a command line to initiate a multiplayer session in which you are joining an existing session, click Start, click Run, and then type the following in the Open box (or at the MS-DOS prompt):
monster.exe /j:NNN.NNN.NNN.NN
(replace Ns with the Internet protocol (IP) address of the host you want to join)
http://forum.mtm2.com/viewtopic.php?p=14052#14052