Limiting one client per IP seems to be a new feature. People on the same network or router cannot play on the same server.
It would be nice to be able to play on the same server with people on your same network - like before.
It is a gameserver config option.
game.allowmultiip = true
by setting this to 'false' one prevent people with same IP address to connect. And this is mostly done due to the fact that there are many cheaters out there who wants to get easy frags by shooting themselves as another connected player.
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