Hi,
I'm following the Server Configuration documentation and came across:
We assume that you have already installed the external database server, and have it running. You should create an empty database named jboss, accessible via the username / password pair jbossuser / jbosspass. The jboss database is used to store JBoss AS internal data -- JBoss AS will automatically create tables and data in it.
Please do not cross-post http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4213839