diff --git a/include/osgSim/DOFTransform b/include/osgSim/DOFTransform
index b4ba8592c..fd7e6eaf0 100644
--- a/include/osgSim/DOFTransform
+++ b/include/osgSim/DOFTransform
@@ -100,11 +100,11 @@ class OSGSIM_EXPORT DOFTransform : public osg::Transform
             RHP
         };
 
-        void setHPRMultOrder(const MultOrder order) {_multOrder = order;}
+        void setHPRMultOrder(const MultOrder order) { _multOrder = order; }
         inline const MultOrder getHPRMultOrder() const { return _multOrder;}
 
-        inline void setAnimationOn(bool do_animate) {_animationOn = do_animate;}
-        inline bool getAnimationOn() const {return _animationOn;}
+        void setAnimationOn(bool do_animate);
+        inline bool getAnimationOn() const { return _animationOn; }
 
         void animate(float deltaTime);
 
diff --git a/src/osgSim/DOFTransform.cpp b/src/osgSim/DOFTransform.cpp
index 3625fb5e8..b6c55bd7e 100644
--- a/src/osgSim/DOFTransform.cpp
+++ b/src/osgSim/DOFTransform.cpp
@@ -34,7 +34,6 @@ DOFTransform::DOFTransform():
     _increasingFlags(0xffff),
     _multOrder(PRH)
 {
-    setNumChildrenRequiringUpdateTraversal(1);
 }
 
 DOFTransform::DOFTransform(const DOFTransform& dof, const osg::CopyOp& copyop):
@@ -60,7 +59,7 @@ DOFTransform::DOFTransform(const DOFTransform& dof, const osg::CopyOp& copyop):
     _increasingFlags(dof._increasingFlags),
     _multOrder(dof._multOrder)
 {
-    setNumChildrenRequiringUpdateTraversal(getNumChildrenRequiringUpdateTraversal()+1);            
+    if (_animationOn) setNumChildrenRequiringUpdateTraversal(getNumChildrenRequiringUpdateTraversal()+1);            
 }
 
 void DOFTransform::traverse(osg::NodeVisitor& nv)
@@ -460,6 +459,20 @@ void DOFTransform::updateCurrentScale(const osg::Vec3& scale)
     dirtyBound();
 }
 
+void DOFTransform::setAnimationOn(bool do_animate)
+{
+    if (_animationOn == do_animate) return;
+    
+    int delta = 0;
+
+    if (_animationOn) --delta;
+    if (do_animate) ++delta;
+
+    _animationOn = do_animate;
+    
+    if (_animationOn) setNumChildrenRequiringUpdateTraversal(getNumChildrenRequiringUpdateTraversal()+delta);
+}
+
 void DOFTransform::animate(float deltaTime)
 {
     if(!_animationOn) return;