I have a similar problem with the new one.
I have a feeling that this is a problem with XP SP2. I got a fireall warning, but still couldn't connect after allowing it through. The console shows me these errors:
Unable to connect : java.net.SocketException : Software caused connection abort: connect
Connecting...
Unable to connect : java.net.SocketException : Software caused connection abort: connect
Connecting...
Unable to connect : java.lang.NullPointerException
Connecting...
Unable to connect : java.net.SocketException : Software caused connection abort: connect
Connecting...
Unable to connect : java.lang.NullPointerException
Connecting...
Unable to connect : java.net.SocketException : Software caused connection abort: connect
Connecting...
Unable to connect : java.lang.NullPointerException
Connecting...
Unable to connect : java.net.SocketException : Software caused connection abort: connect
Connecting...
Unable to connect : java.lang.NullPointerException
When I get a chance I'll try this on my wife's Win2K box.