Eddie,
Nate's program displays a window sort of like an AIM alert when someone joins or leaves the chatroom. AFAIK, mIRC doesn't do this. You don't need to know when people join or leave if the mIRC window is already open
Nate.
It doesn't seem to be responding to all the right protocol. After running it for a few minutes, you get a ping timeout.
I figure you probably want to do this to learn the IRC protocol, but it seems like it would be a lot easier to use a combination of an mIRC script using ON JOIN and /run and an external program.