Problems returning interfaces

[Leonardo Mena]

I have been trying to expose my app as a set of web services with Axis but can't resolve how to correctly export an interface. That is, some web service method returns an interface instead of a JavaBean (of course the concrete implementation is a JavaBean).   I tried mapping the interface to the concrete JavaBean but still have problems: an exception occurs with the message can't instantiate TreeFolder, but is the interface! I don't uinderstand why Axis tries to instantiate the interface...   Any sugestion? Leo     DETAIL AxisFault  faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException  faultSubcode:  faultString: org.xml.sax.SAXException: Unable to create JavaBean of type yae.server.plugins.services.organizer.TreeFolder.  Missing default constructor?  Error was: java.lang.InstantiationException: yae.server.plugins.services.organizer.TreeFolder.  faultActor:  faultNode:  faultDetail:  {http://xml.apache.org/axis/}stackTrace: AxisFault  faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException  faultSubcode:  faultString: org.xml.sax.SAXException: Unable to create JavaBean of type yae.server.plugins.services.organizer.TreeFolder.  Missing default constructor?  Error was: java.lang.InstantiationException: yae.server.plugins.services.organizer.TreeFolder.  faultActor:  faultNode:  faultDetail: