How to change the message

I have seen many wiki's, where it says when you get a message, stuff like: "Bearing ye message" I can't figure out how I can do that. I went through the system messages, I didn't see anything. Does anyone here know how to do that? (the messages where it says: You have a new message) I want to change that. Ruler of the Coasters 11:40, March 9, 2012 (UTC)