Private games?

[Itchykobu]

Is there a way to set up a private match? I was hoping that the --masterpass flag would mean that players have to enter that password to play, but I just tested it with a friend and that doesn't seem to be what it does at all.

I've got a bunch of friends drawing from the same pool of ports on my server and it would be nice to allow them all to be able to set up games against selective opponents w/out the hassle of someone else accidentally (or maliciously) joining.

Thanks.