Shoutbox

I'm totally new to this and really don't know how to configure this script.  Perhaps a step by step for beginners is needed.

In the meantime, all I really need for now is something I can set to auto respond when I choose to be unavailable.  Something like "I'm unavailable right now.  Hang in there, I'll be right back!" and have it configured so that it doesn't matter what the other person types, it will always show that message.

Thanks in advance and I hope to be using this soon!