Sir Laurence Olivier never played a character of that name.

This isn't specifically intended for Bob Newhart, but I kind of think that shows where the star gets to have the same name as they actually have in real life (According to Jim, for instance) are pretty pointedly indicating that the stars of the shows are such poor actors they can't be counted on to remember to turn their heads when a co-star says their character's name if it happens to be different than their own. I guess if I ever have a son, I'll name him Hamlet. So when they make a sitcom called that he can star in it.