So, not to point finger (or wings) at anyone, but it's become quite a common thing for there to be multiple OCs that have the same name. Yes, it's not exactly a HUGE problem, but still, on one likes being told that someone else has already used a certain name -- especially when you put a lot of thought into it. Well, it's actually easer then you might think to figure out if a name has already been used: just use the search option.
Right below the icon you click to enter the MB (it says 'MESSAGE BOARD' on it), there's a little box that says search. Whenever you create a new OC, just type the name into the box, wait a few seconds, and see if the name has been mentioned before. Ta da! No more repeated names.