I did a little more investigation and compared the JNDI InitialContext environment on two different machines -- one which works and the one which doesn't. On the machine that works, new InitialContext()'s environment has no java.naming.provider.url property. On the machine that's having this problem, new InitialContext's environment has java.naming.provider.url=localhost. This property is NOT one of the system properties: I dumped System.getProperties().entrySet() immediately before the first failing lookup and java.naming.provider.url is not one of the properties. What could be setting this property? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4048444#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...