The JBoss default root page probably might need a change to be more dynamic, based on the server profile that's being run. With JBoss-5 GA, there's a "web" server under %JBOSS_HOME%/server/web. This server profile does not seem to be deploying the "web-console" application. When the root home page is accessed at http://localhost:8080, it has a link to "JBoss Web Console" which when clicked leads to http://localhost:8080/web-console and obviously fails with 404 "The requested resource (/web-console/) is not available." error.
Thinking more about this, should the root page be having links to applications deployed within the server? What if the web-console or jmx-console are intentionally not deployed by the user? The root page will still continue to show those links.