*First: I realize this won't ever be seamless, but I just want to know the possibilities/possible implementations and what they would look like. I realize you would have to switch clients or have to use a workaround. I'm not expecting anything to come up, and this is probably an absurd question, but I thought I'd ask anyways. What I'm looking for is a server where one world is, say, 1.4.7 Beta, and the other world is 1.2.6 Alpha (or just an earlier version). Im sort of split; half my server likes the nostalgic feel of alpha while the other half refuses to even try it. The only thing I can think of is running two servers on different ports, but that's resource demanding and then you just have... two servers. Is there any way you could host one server with two different versions? Could the modding API make this easier?