The definite answer is, it can be done but an Admin has to do it.
We don't do it unless there is a valid reason. The only one I've done was a guy who's name referenced a faith he had left. So unless you happen to be BuddistBackpacker and you want to change it up to SitkaSihk don't ask.
I tried to change my handle a while back to get "kill" out of the name since I use Rokslide at work sometimes. I never got a response so that didn't seem to be a valid enough reason either. I haven't been fired yet so no worries, think I'll stick with this one!