The tomcat examples contain a lot of example
configurations which tomcat standalone ignores
but jboss doesn't. You will need to fix that
config, it is broken. e.g. ejb-ref
I just started teaching myself Servlets and JSP last week, using Tomcat 4.1.18 (from Apache). After several hours of digging around, the only way I've been able to make servlets work is to include a <servlet-mapping> section in the web.xml file for each servlet.
I seem to remember reading about a master servlet that would automatically deploy servlets without <servlet-mapping> information, but that it had been disabled in current versions of Tomcat.
Hope this helps!