Play a sound when chat invitation occurs

hello all,

I just downloaded and installed Spark, and I am trying to configure it so if I am turned away from my machine, and I receive a request to join a conference, I can have a sound play, but don’'t see a way to do this. There must be a way, can someone help explain how to do this? I see the options to select for incoming messages, outgoing messages, change status, but nothing for an incoming request.

thanks very much,