diff --git a/include/osgAnimation/Interpolator b/include/osgAnimation/Interpolator
index 1190e3aa4..28c9b789f 100644
--- a/include/osgAnimation/Interpolator
+++ b/include/osgAnimation/Interpolator
@@ -33,33 +33,29 @@ namespace osgAnimation
         typedef TYPE UsingType;
 
     public:
-        mutable int _lastKeyAccess;
+        TemplateInterpolatorBase() {}
 
-        TemplateInterpolatorBase() : _lastKeyAccess(-1) {}
-
-        void reset() { _lastKeyAccess = -1; }
         int getKeyIndexFromTime(const TemplateKeyframeContainer<KEY>& keys, double time) const
         {
-            // todo use a cache
             int key_size = keys.size();
             if (!key_size) {
                 osg::notify(osg::WARN) << "TemplateInterpolatorBase::getKeyIndexFromTime the container is empty, impossible to get key index from time" << std::endl;;
                 return -1;
             }
             const TemplateKeyframe<KeyframeType>* keysVector = &keys.front();
-            for (int i = 0; i < key_size-1; i++)
-            {
-                double time0 = keysVector[i].getTime();
-                double time1 = keysVector[i+1].getTime();
-
-                if ( time >= time0 && time < time1 )
-                {
-                    _lastKeyAccess = i;
-                    return i;
+            int k = 0;
+            int l = key_size;
+            int mid = key_size/2;
+            while(mid != k){
+                double time1 = keysVector[mid].getTime();
+                if(time1 < time){
+                    k = mid;
+                } else {
+                    l = mid;
                 }
+                mid = (l+k)/2;
             }
-            osg::notify(osg::WARN) << time << " first key " << keysVector[0].getTime() << " last key " << keysVector[key_size-1].getTime() << std::endl;
-            return -1;
+            return k;
         }
     };
 
diff --git a/src/osgAnimation/StackedTransform.cpp b/src/osgAnimation/StackedTransform.cpp
index 91ac2d842..a56b35f1a 100644
--- a/src/osgAnimation/StackedTransform.cpp
+++ b/src/osgAnimation/StackedTransform.cpp
@@ -32,7 +32,7 @@ StackedTransform::StackedTransform(const StackedTransform& rhs, const osg::CopyO
 
 void StackedTransform::update(float t)
 {
-    int dirty = 0;
+    bool dirty = false;
     for (StackedTransform::iterator it = begin(); it != end(); ++it)
     {
         StackedTransformElement* element = it->get();
@@ -40,9 +40,9 @@ void StackedTransform::update(float t)
             continue;
         // update and check if there are changes
         element->update(t);
-        if (element->isIdentity())
-            continue;
-        dirty++;
+        if (!dirty && !element->isIdentity()){
+            dirty = true;
+        }
     }
 
     if (!dirty)
diff --git a/src/osgAnimation/UpdateBone.cpp b/src/osgAnimation/UpdateBone.cpp
index cbc50ba3a..eb892a076 100644
--- a/src/osgAnimation/UpdateBone.cpp
+++ b/src/osgAnimation/UpdateBone.cpp
@@ -46,9 +46,9 @@ void UpdateBone::operator()(osg::Node* node, osg::NodeVisitor* nv)
 
         Bone* parent = b->getBoneParent();
         if (parent)
-            b->setMatrixInSkeletonSpace(b->getMatrixInBoneSpace() * parent->getMatrixInSkeletonSpace());
+            b->setMatrixInSkeletonSpace(matrix * parent->getMatrixInSkeletonSpace());
         else
-            b->setMatrixInSkeletonSpace(b->getMatrixInBoneSpace());
+            b->setMatrixInSkeletonSpace(matrix);
     }
     traverse(node,nv);
 }