When I describe the servlet mapping in the web.xml file the url-pattern "/*" means "match all requests". Can I specify the url-pattern like "match all except *.jsp" ?

Unfortunately... I don't think you can do that.

[Alessandro A. Garbagnati, Feb 20, 2002 adds:
Since Tom's suggestion did not work, I'm afraid you need to put something in your servlet that will just forward the request to the jsp page when the request is a jsp page. ]