Well, his quits could be done with:
on ^*:QUIT:{ if ($nick == nick) { haltdef } }
His away message is a bit harder, because I have no idea whether it's a msg to the channel or a notice or an action. The approach would probably be the same. Use TEXT, ACTION or NOTICE depending on what it is. Also, put something as "sometext" which identifies his away message, like for instance "I am now away".
on ^*:TEXT/ACTION/NOTICE:*sometext*:#:{ if ($nick == nick) { haltdef } }