I can't use Map or HashMap as a return parameter in my Web Service even if I wrap it in another class. It keeps raising: javax.xml.bind.JAXBException: class java.util.HashMap nor any of its super class is known to this context Isn't Map supposed to be supported by default ? Can anyone provide me a working example to use Map and HashMap in Web Services (JAX-WS). Thanks in advance. Antonio Souza. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4144352#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...