Hi Peter, thanks for your help. If I move the class package.Foo to foo.par entity module, the common.jar under server/default/lib can instantiate the class. But the package.Foo class needs to access classes defined in the web module, and throws java.lang.NoClassDefFoundError. Is there a way for entity module to access war module? or can I configure some classloader to make it work? Thanks Dave View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4132026#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...