diff --git a/include/osg/NodeVisitor b/include/osg/NodeVisitor
index 842b8b791..d94574ff0 100644
--- a/include/osg/NodeVisitor
+++ b/include/osg/NodeVisitor
@@ -194,13 +194,14 @@ class SG_EXPORT NodeVisitor : public Referenced
         
         virtual void apply(Geode& node)                     { apply((Node&)node); }
         virtual void apply(Billboard& node)                 { apply((Geode&)node); }
-        virtual void apply(LightSource& node)               { apply((Node&)node); }
-        virtual void apply(ClipNode& node)                  { apply((Node&)node); }
         
         virtual void apply(Group& node)                     { apply((Node&)node); }
 
         virtual void apply(Projection& node)                { apply((Group&)node); }
 
+        virtual void apply(ClipNode& node)                  { apply((Group&)node); }
+        virtual void apply(LightSource& node)               { apply((Group&)node); }
+
         virtual void apply(Transform& node)                 { apply((Group&)node); }
         virtual void apply(DOFTransform& node)              { apply((Transform&)node); }
         virtual void apply(MatrixTransform& node)           { apply((Transform&)node); }
diff --git a/src/osgUtil/CullVisitor.cpp b/src/osgUtil/CullVisitor.cpp
index 13c3c0667..2e2032794 100644
--- a/src/osgUtil/CullVisitor.cpp
+++ b/src/osgUtil/CullVisitor.cpp
@@ -58,8 +58,8 @@ class PrintVisitor : public NodeVisitor
 
         virtual void apply(Geode& node)         { apply((Node&)node); }
         virtual void apply(Billboard& node)     { apply((Geode&)node); }
-        virtual void apply(LightSource& node)   { apply((Node&)node); }
-        virtual void apply(ClipNode& node)      { apply((Node&)node); }
+        virtual void apply(LightSource& node)   { apply((Group&)node); }
+        virtual void apply(ClipNode& node)      { apply((Group&)node); }
         
         virtual void apply(Group& node)         { apply((Node&)node); }
         virtual void apply(Transform& node)     { apply((Group&)node); }
@@ -382,6 +382,8 @@ void CullVisitor::apply(LightSource& node)
         addPositionedAttribute(&matrix,light);
     }
 
+    handle_cull_callbacks_and_traverse(node);
+
     // pop the node's state off the geostate stack.    
     if (node_state) popStateSet();
 }
diff --git a/src/osgUtil/Optimizer.cpp b/src/osgUtil/Optimizer.cpp
index f6176a1eb..53a9d2ee2 100644
--- a/src/osgUtil/Optimizer.cpp
+++ b/src/osgUtil/Optimizer.cpp
@@ -933,7 +933,8 @@ void Optimizer::RemoveEmptyNodesVisitor::apply(osg::Group& group)
     if (group.getNumParents()>0)
     {
         // only remove empty groups, but not empty occluders.
-        if (group.getNumChildren()==0 && !dynamic_cast<osg::OccluderNode*>(&group))
+        if (group.getNumChildren()==0 && 
+            (typeid(group)==typeid(osg::Group) || dynamic_cast<osg::Transform*>(&group)))
         {
             _redundentNodeList.insert(&group);
         }