I get my ID nicely from
https://socketio.mtgox.com/socket.io/1/ but then after I connect my websocket lib to ws://socketio.mtgox.com:80/socket.io/1/websocket/XXXXX - it just sends me "7:::1+0" and disconnects immediately after that.
If u got ID from https:// than u must connect to wss:// with this ID (SSL/TLS - secure connection)
and if http:// than ws://