according to a post on GSC forums by a GSC moderator, MP is lan only.
"Unfortunatelly, the publisher inserted the wrong manual. The MP mode supports up to 32 players and works via LAN only. We are currently bringing this issue up with the publisher . I am not sure if there will be a MP patch."
 uh, yeah, what Enahs said...
This comment was edited on Dec 8, 15:20.