In the JB 4.2.3 documentation, description of the above-captioned parameter is vague: DownloadServerClasses: A flag indicating if the server should attempt to download classes from thread context class loader when a request arrives that does not have a class loader key prefix. Not sure what the ramifications are to leave to default setting to true or to set it to false. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4204425#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...