Shoutbox

I was wondering...how would I make it so that when someone opens an IM window with me that I could send a message automatically to them after or before they send any text.  Kinda like the encarta bot does?  Any one have an idea.  This is what I have but I'm pretty sure it'll be wrong.

code:

---

function OnEvent_ChatWndSendMessage(
[object] ChatWnd,
[string] Message

var Message = "Hello " + Contact::Name + "!";

return Message;
);

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