Use onChatMessage.
It can be used to easily edit, get, and use the message, and only has 3 variables. You don't even need to package it, or parent it!
No seriously, don't package or parent it. Seriously don't.
Here's a snippet of code:
function onChatMessage(%message, %voice, %pitch)
{
newChatHud_addLine(%message);
//dostuff here
}
Or if you want to modify the message, you can edit %message before the newChatHud_blah line.