Shoutbox

Hello again, I am trying to change the button to close out the toasts when an email arrives or when someone starts session.
Try in any way but I could not. If someone could help me please to know the exact code.
I have Windows Live Messenger version 8.5

This is the button that want to change by a Vista Aero Style

And I want the button look like this:



I post here because in the forum in Spanish as many answers as there is in this. And I learned something of xml using the Skinning Documentation.  Thanks, Bye.