Have someone that wants a grooms cake like the mad hatters hat in Alice in Wonderland. Is the hat copyrighted or just the character him self?

Alice In Wonderland is not copyrighted anymore. It is too old. You can make an Alice cake and any of the characters.

What you cannot do is copy the old Disney cartoon or the new movie. Those are protected.

I made an Alice cake and all of the little characters and symbols. But I did my own interpretation, including the hat. I made sure they did not resemble the two movies. Pictures are on my site. It was obvious to anyone that it was an Alice cake.