From Rafa Giatan and Robert Osfield, added support for User defined events, by adding

UserData to Events.

src/osgGA/EventQueue.cpp

@@ -358,3 +358,15 @@ GUIEventAdapter* EventQueue::createEvent()
     if (_accumulateEventState.valid()) return new GUIEventAdapter(*_accumulateEventState.get()); 
     else return new GUIEventAdapter();    
 }
+
+void EventQueue::userEvent(osg::Referenced* userEventData, double time)
+{
+    GUIEventAdapter* event = new GUIEventAdapter(*_accumulateEventState);
+    event->setEventType(GUIEventAdapter::USER);
+    event->setUserData(userEventData);
+    event->setTime(time);
+    
+    addEvent(event);
+};
+
+

src/osgGA/GUIEventAdapter.cpp

@@ -41,8 +41,8 @@ GUIEventAdapter::GUIEventAdapter():
     _tabletPointerType(UNKNOWN)
 {}
 
-GUIEventAdapter::GUIEventAdapter(const GUIEventAdapter& rhs):
-    osg::Referenced(),
+GUIEventAdapter::GUIEventAdapter(const GUIEventAdapter& rhs,const osg::CopyOp& copyop):
+    osg::Object(rhs,copyop),
     _handled(rhs._handled),
     _eventType(rhs._eventType),
     _time(rhs._time),