ok here you go
code:
function OnEvent_ChatWndReceiveMessage(ChatWnd,Origin,Message)
{
if(Message=='moo!')
{
g = new Array('word','something','stuff','goes','here'); //the words you want
ran = g[Math.floor(Math.random()*g.length)]; //getting a random word
ChatWnd.SendMessage(ran); //sending the word
}
}
tested it as well and it works fine so have fun