Hi. I have just installed jboss AS 4.0.4CR2 with the jar installer from the download page and I was not able to run the server because:
/bin/run.sh results in: "Failed to boot JBoss: .../default/conf/jboss-service.xml could not be open..."
In the installation process: -> I choose to name my configuration MyConf (not default) -> The installer tell that if you want to start the server with your configuration, you must use the -c option with run.sh
So to run your server, just start: run.sh -c MyConf
Hope that this will help you not to lose your time like me in the too big JBoss forum.