Not currently, with out changing the source.
I believe that there are a couple other people that want to do this and its been discussed here in the forums. You may want to search for it as I seem to recall that they were having some luck in the body section at least.
This might help: http://www.osticket.com/forums/showthread.php?t=14165(http://www.osticket.com/forums/showthread.php?t=14165)