web.xml needs to be in a directory called WEB-INF under your apps webapps dir.
The structure of your app should be as follows:
webapps/YOUR_APP_NAME/JSPS, HTML
webapps/YOUR_APP_NAME/WEB-INF/web.xml
webapps/YOUR_APP_NAME/WEB-INF/classes/YOUR_PACKAGE/YOUR_CLASSES
You'll also need to map your servlets (in web.xml)
The invoker servlet is no longer active by default in Tomcat.
You don't need '/servlet' in your URL once you map the servlet.
You also don't need to (and shouldn't) create a context entry in server.xml anymore. Check with the Tomcat documention for proper deployment procedures in version 5 and up.
If you want an example of a proper web.xml with a servlet mapping and the correct directory structure for a webapp, go to
http://simple.souther.us, download and run SimpleServlet.
Tomcat will unpack the war file for you. You can then examine both the directory structure and the web.xml file to see what's different in your app that's keeping it from working.
-Ben
[ January 22, 2005: Message edited by: Ben Souther ]