diff --git a/include/osg/observer_ptr b/include/osg/observer_ptr
index f2d315b4f..aca5eca0b 100644
--- a/include/osg/observer_ptr
+++ b/include/osg/observer_ptr
@@ -40,9 +40,10 @@ class observer_ptr : public Observer
 
         observer_ptr(): _ptr(0L)                            {}
         observer_ptr(T* t): _ptr(t)                         { if (_ptr) _ptr->addObserver(this); }
-        observer_ptr(const observer_ptr& rp): _ptr(0L)
+        observer_ptr(const observer_ptr& rp)
         {
             OpenThreads::ScopedLock<OpenThreads::Mutex> lock(*getObserverMutex());
+            _ptr = rp._ptr;
             if (_ptr) _ptr->addObserver(this);
         }