As for cookies 'having' to be enabled... one thing to remember about URL re-writing is that it only really applies to URLs that you would send to a client...
So if you're doing server-side things like <jsp:include ../> or <jsp:forward .../> the URLs you're using don't *need* to be re-written. Because those URLs are not being turned into clickable links. They are actually not URLs! They're resource paths.
Right! We're on it! Let's get to work tiny ad!
Building a Better World in your Backyard by Paul Wheaton and Shawn Klassen-Koop