Geht momentan wohl nur über Umwege. Aber später vielleicht auch ohne:

Originally Posted By: jcl
We'll implement full clipping for panels and texts. It's too late for the next update, but can make it into the next-but-one. I'll also look into CEGUI.

http://www.opserver.de/ubb7/ubbthreads.php?ubb=showflat&Number=364817#Post364817