1) As all you need to change the call script is tinker with the XML you return to the Twillo server upon incoming call, making it dependent on your IM status so

1) As all you need to change the call script is tinker with the XML you return to the Twillo server upon incoming call, making it dependent on your IM status so long as you have an API for it is trivial. 2) Not really sure about this one, but my guess would be that he is reusing the Nginx server in-front of the Rails app.