The web-app_2_3.dtd spec indicates that the element "res-ref-name" (as found in web.xml/resource-ref) is a JNDI name relative to java:comp/env. For example, in my setup, I put "jdbc/juddiDB". I've configured a datasource in my deploy directory to have the jndi-name element with a value of "comp/env/jdbc/juddiDB" (it's relative to the scheme java:). Well then why isn't this sufficient? When JBoss tries to deploy my web-app, it fails because there is no jboss-web.xml file with a resource-ref JNDI binding. I argue it isn't necessary.