diff --git a/include/osg/BlendFunc b/include/osg/BlendFunc
index d2cb3d2a4..ec73cf8e9 100644
--- a/include/osg/BlendFunc
+++ b/include/osg/BlendFunc
@@ -15,6 +15,7 @@
 #define OSG_BLENDFUNC 1
 
 #include <osg/StateAttribute>
+#include <osg/GLExtensions>
 
 
 #ifndef GL_VERSION_1_2
@@ -157,54 +158,25 @@ class OSG_EXPORT BlendFunc : public StateAttribute
         inline GLenum getDestinationAlpha() const { return _destination_factor_alpha; }
 
         virtual void apply(State& state) const;
+
         /** Encapsulates queries of extension availability, obtains extension
         * function pointers, and provides convenience wrappers for
         * calling extension functions. */
-        class OSG_EXPORT Extensions : public osg::Referenced
+        struct Extensions : public osg::Referenced
         {
-        public:
-            Extensions(unsigned int contextID);
+            bool isBlendFuncSeparateSupported;
+            void (GL_APIENTRY * glBlendFuncSeparate) (GLenum sfactorRGB, GLenum dfactorRGB, GLenum sfactorAlpha, GLenum dfactorAlpha) ;
 
-            Extensions(const Extensions& rhs);
-
-            void lowestCommonDenominator(const Extensions& rhs);
-
-            void setupGLExtensions(unsigned int contextID);
-
-            void setBlendFuncSeparateSupported(bool flag) { _isBlendFuncSeparateSupported=flag; }
-            bool isBlendFuncSeparateSupported() const { return _isBlendFuncSeparateSupported; }
-
-            void glBlendFuncSeparate(GLenum sfactorRGB,
-                                     GLenum dfactorRGB,
-                                     GLenum sfactorAlpha,
-                                     GLenum dfactorAlpha) const;
-
-        protected:
-
-            ~Extensions() {}
-
-
-            typedef void (GL_APIENTRY * GLBlendFuncSeparateProc) (GLenum sfactorRGB,
-                                                               GLenum dfactorRGB,
-                                                               GLenum sfactorAlpha,
-                                                               GLenum dfactorAlpha);
-            bool                    _isBlendFuncSeparateSupported;
-            GLBlendFuncSeparateProc _glBlendFuncSeparate;
+            Extensions(unsigned int contextID)
+            {
+                isBlendFuncSeparateSupported = OSG_GLES2_FEATURES || OSG_GL3_FEATURES ||
+                                                osg::isGLExtensionSupported(contextID, "GL_EXT_blend_func_separate") ||
+                                                strncmp((const char*)glGetString(GL_VERSION), "1.4", 3) >= 0;
 
+                setGLExtensionFuncPtr(glBlendFuncSeparate, "glBlendFuncSeparate", "glBlendFuncSeparateEXT");
+            }
         };
 
-        /** Returns the Extensions object for the given context.
-        * If createIfNotInitalized is true and the Extensions object doesn't
-        * exist, getExtensions() creates it on the given context.
-        * Returns NULL if createIfNotInitalized is false and the Extensions
-        * object doesn't exist. */
-        static Extensions* getExtensions(unsigned int contextID,bool createIfNotInitalized);
-
-        /** setExtensions() allows users to override the extensions across graphics contexts.
-        * Typically used when you have different extensions supported across graphics pipes,
-        * but need to ensure that they all use the same low common denominator extensions. */
-        static void setExtensions(unsigned int contextID,Extensions* extensions);
-
 
     protected :
 
diff --git a/include/osg/State b/include/osg/State
index 64beb580d..85cc23ea4 100644
--- a/include/osg/State
+++ b/include/osg/State
@@ -150,6 +150,37 @@ class OSG_EXPORT State : public Referenced
         inline unsigned int getContextID() const { return _contextID; }
 
 
+        // ExtensionMap contains GL Extentsions objects used by StateAttribue to call OpenGL extensions/advanced features
+        typedef std::map<const std::type_info*, osg::ref_ptr<osg::Referenced> > ExtensionMap;
+        ExtensionMap _extensionMap;
+
+        /** Get a specific GL extensions object, initialize if not already present.
+          * Note, must only be called from a the graphics context thread associated with this osg::State. */
+        template<typename T>
+        T* get()
+        {
+            const std::type_info* id(&typeid(T));
+            osg::ref_ptr<osg::Referenced>& ptr = _extensionMap[id];
+            if (!ptr)
+            {
+                ptr = new T(_contextID);
+            }
+            return static_cast<T*>(ptr.get());
+        }
+
+        /** Get a specific GL extensions object if it already exists in the extension map.
+          * Note, safe to call outwith a the graphics context thread associated with this osg::State.
+          * Returns NULL if the desired extension object has not been created yet.*/
+        template<typename T>
+        const T* getExisting() const
+        {
+            const std::type_info* id(&typeid(T));
+            ExtensionMap::const_iterator itr = _extensionMap.find(id);
+            if (itr==_extensionMap.end()) return 0;
+            else return itr->second.get();
+        }
+
+
         /* Set whether shader composition is enabled.*/
         void setShaderCompositionEnabled(bool flag) { _shaderCompositionEnabled = flag; }
 
diff --git a/src/osg/BlendFunc.cpp b/src/osg/BlendFunc.cpp
index 5c8c905fd..054e856e0 100644
--- a/src/osg/BlendFunc.cpp
+++ b/src/osg/BlendFunc.cpp
@@ -50,13 +50,8 @@ void BlendFunc::apply(State& state) const
     if (_source_factor != _source_factor_alpha ||
         _destination_factor != _destination_factor_alpha)
     {
-        // get the contextID (user defined ID of 0 upwards) for the
-        // current OpenGL context.
-        const unsigned int contextID = state.getContextID();
-
-        const Extensions* extensions = getExtensions(contextID,true);
-
-        if (!extensions->isBlendFuncSeparateSupported())
+        const Extensions* extensions = state.get<Extensions>();
+        if (!extensions->isBlendFuncSeparateSupported)
         {
             OSG_WARN<<"Warning: BlendFunc::apply(..) failed, BlendFuncSeparate is not support by OpenGL driver, falling back to BlendFunc."<<std::endl;
         }
@@ -69,61 +64,3 @@ void BlendFunc::apply(State& state) const
 
     glBlendFunc( _source_factor, _destination_factor );
 }
-
-
-typedef buffered_value< ref_ptr<BlendFunc::Extensions> > BufferedExtensions;
-static BufferedExtensions s_extensions;
-
-BlendFunc::Extensions* BlendFunc::getExtensions(unsigned int contextID,bool createIfNotInitalized)
-{
-    if (!s_extensions[contextID] && createIfNotInitalized) s_extensions[contextID] = new Extensions(contextID);
-    return s_extensions[contextID].get();
-}
-
-void BlendFunc::setExtensions(unsigned int contextID,Extensions* extensions)
-{
-    s_extensions[contextID] = extensions;
-}
-
-
-BlendFunc::Extensions::Extensions(unsigned int contextID)
-{
-    setupGLExtensions(contextID);
-}
-
-BlendFunc::Extensions::Extensions(const Extensions& rhs):
-    Referenced()
-{
-    _isBlendFuncSeparateSupported = rhs._isBlendFuncSeparateSupported;
-    _glBlendFuncSeparate = rhs._glBlendFuncSeparate;
-}
-
-void BlendFunc::Extensions::lowestCommonDenominator(const Extensions& rhs)
-{
-    if (!rhs._isBlendFuncSeparateSupported)  _isBlendFuncSeparateSupported = false;
-    if (!rhs._glBlendFuncSeparate)           _glBlendFuncSeparate = 0;
-}
-
-void BlendFunc::Extensions::setupGLExtensions(unsigned int contextID)
-{
-    _isBlendFuncSeparateSupported = OSG_GLES2_FEATURES || OSG_GL3_FEATURES ||
-                                    isGLExtensionSupported(contextID, "GL_EXT_blend_func_separate") ||
-                                    strncmp((const char*)glGetString(GL_VERSION), "1.4", 3) >= 0;
-
-     setGLExtensionFuncPtr(_glBlendFuncSeparate, "glBlendFuncSeparate", "glBlendFuncSeparateEXT");
-}
-
-void BlendFunc::Extensions::glBlendFuncSeparate(GLenum sfactorRGB,
-                                                GLenum dfactorRGB,
-                                                GLenum sfactorAlpha,
-                                                GLenum dfactorAlpha) const
-{
-    if (_glBlendFuncSeparate)
-    {
-        _glBlendFuncSeparate(sfactorRGB, dfactorRGB, sfactorAlpha, dfactorAlpha);
-    }
-    else
-    {
-        OSG_WARN<<"Error: glBlendFuncSeparate not supported by OpenGL driver"<<std::endl;
-    }
-}