Tomcat 4.0

I have an older version of Tomcat working with Jigsaw (Tomcat 3.0) and I
am trying to integrate Tomcat 4.0 with Jigsaw.  I have run into a couple
of problems, for instance there are several classes that do not compile
with the new Servlet engine (version 2.3), because of new abstract
methods that need to be implemented when extending classes such as
HttpServletRequest, HttpServletResponse and HttpSession.  
 
I was wondering if Jigsaw was planning on supporting Tomcat 4.0
integration anytime in the near future or if there was any information
on how to do this?  
 
Thank you,
George