Smooth animation between two classes (font-family tag, in particular)

I'm looking to create the effect of a smooth animation between two different words and two different type faces. Ideally this would occur on click or hover, I'm not picky about that part of it. Basically, a smooth morph between two css classes.

I looked into the js .animate() function, but that is only for numerical values. I also tried MooTools FX.Tween but that didn't seem to work either.

Think the Michael Jackson video for "Black or White", but with font-family.

Thanks in advance for any guidance.

The only thing that comes to mind:

http://raphaeljs.com/

http://raphaeljs.com/helvetica.html

If it can morph between different letters, with extra work it can do what you want.

I do not think this is possible because, as you said, animations must be performed on numerical values (background color, width, height, position). You could only model font faces with really complex numbers.