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.