Yeah, you can launch a "fake" dedicated server, ie: with a fast host, just setup a game to rotate based on score limit + time limit (a good example is every 50 minutes/50 frags). Then post the IP on the IP boards and perhaps let folks on the Zone/GameSpyArcade know about it.
Then keep it up as long as you can. I would suggest checking on it every so often with Kicker Helper to make sure nobody is "hacking" the game up. The DKB clan was running (or maybe still running) a very good "Dedicated" MotS server (which began many months ago).
JK is based on a peer-to-peer network model and is not client/server, so a "true" DS is not really possible without reworking parts of the netcode. LEC recieved a petition about it from the fans but said it was too much work for them.