Shoutbox

I'm guessing your messenger is set to sign in automatically. When opening another messenger this pretty much means it's going to sign in again, resulting in your already signed in messenger signing out. To solve this either lunge for the contact list and click cancel once your second messenger opens, or next time you sign in untick sign in automatically, and then sign in to apply that setting. I think there was a script somewhere which controlled this even further (allowing for specific emails to sign into the second messenger upon opening) however I can't remember the name of it.