Forum:How to change automatic message on talk pages?

Ok. I'm probably the only wiki admin on earth that doesn't know how to do this, but how can I change the auto greeting message that is left on the talk pages of new users and unregistered contributors? Thanks in advance. --Klock101 03:12, April 27, 2011 (UTC)

MediaWiki:Welcome-message-user--


 * I didn't know it too ; thanks G.sime :)