I'll have to ask my friend as I'm not sure who he uses as a host as I'm not into those details.
I do have a problem on my singleplayer game though. I mentioned I was building an underwater viewing tunnel. Well, I completed the tunnel last night, and I put doors at each end to close it off, and if I open the doors back up, the water in it doesn't flow anymore, but the problem is that the water is in there at all. Do I use a bucket to scoop the water out?