diff --git a/include/osg/GLExtensions b/include/osg/GLExtensions
index 7388fa4f0..63e46538c 100644
--- a/include/osg/GLExtensions
+++ b/include/osg/GLExtensions
@@ -813,6 +813,9 @@ class OSG_EXPORT GLExtensions : public osg::Referenced
 
         /** convenience wrapper around glObjectLabel that calls glObjectLabel if it's supported and using std::string as a label parameter.*/
         void debugObjectLabel(GLenum identifier, GLuint name, const std::string& label) const { if (glObjectLabel && !label.empty()) glObjectLabel(identifier, name, label.size(), label.c_str()); }
+
+    protected:
+        virtual ~GLExtensions();
 };
 
 
diff --git a/src/osg/GLExtensions.cpp b/src/osg/GLExtensions.cpp
index ed0cd8d61..ead8a058f 100644
--- a/src/osg/GLExtensions.cpp
+++ b/src/osg/GLExtensions.cpp
@@ -1284,6 +1284,13 @@ GLExtensions::GLExtensions(unsigned int in_contextID):
 
 }
 
+GLExtensions::~GLExtensions()
+{
+    // Remove s_gl*List
+    s_glExtensionSetList[contextID] = ExtensionSet();
+    s_glRendererList[contextID] = std::string();
+    s_glInitializedList[contextID] = 0;
+}
 
 ///////////////////////////////////////////////////////////////////////////
 // C++-friendly convenience methods