That's because JBoss 3.0 now forces you to use a WAR file for accessing JSP and servlets via Catalina. It didn't used to be this way, but someone thought it would be better.
Personally, I'm going to try to figure out how to run JBoss and Catalina unbundled so I can use Catalina's features again. Catalina allows you to point your root directory either to a WAR file or to a regular path. An example of this is the way ROOT is configured in server.xml. However, when bundled, server.xml is disabled. Plus, this example is for virtual servers, a feature you need to enable in Catalina.
You can still run Catalina standalone (without JBoss) by runing STARTUP.BAT in Catalina's bin folder. Then, try accessing 8080 again:
You'll get a nice web page with links to examples and stuff. This is how it should be, but I can't find a way to accomplish this with JBoss 3.0 bundled, and none of the developer who might now answered my posts.
The reason it looks so poor when you first bring up the server is that they forgot to include the deployment webtest.ear in the /deploy folder of the JBoss 3.0 release. The examples.war and ROOT.war files are inside webtest.ear.
There was a thread in late July on this subject.
Here's a copy of it -- got it from the thread back in July. I believe, it was a major slip-up to exclude this file.