Actually, I've never seen JSPs being mapped. From what I know you map servlets because, the servlet you define, is just the class name. But you cannot call class names, you need to map it to a url. So it is like saying what is the url of the java-servlet-class you created.
But for JSPs, they can go directly to the url. No mapping is needed.
Now if it can be done I don't know, but I am sure that it is not needed