So how long can your URL be before Tomcat spits the dummy and gives you an HTTP 414 error?
On the site I'm currently working on it is 8208 characters. 8207 works fine, 8208 gives the 414 (Request URI too large). And that is one looooonnnnnnnnnnng URL!
That's using Tomcat 5.5.17 and Java 1.5.0_06-b05