diff --git a/src/osg/GLExtensions.cpp b/src/osg/GLExtensions.cpp
index f6e221a48..30c5a16e3 100644
--- a/src/osg/GLExtensions.cpp
+++ b/src/osg/GLExtensions.cpp
@@ -149,7 +149,7 @@ bool osg::isGLUExtensionSupported(const char *extension)
     if (s_extensions==NULL)
     {
         // get the extension list from OpenGL.
-        s_extensions = (const char*)gluGetString(GL_EXTENSIONS);
+        s_extensions = (const char*)gluGetString(GLU_EXTENSIONS);
         if (s_extensions==NULL) return false;
 
         // insert the ' ' delimiated extensions words into the extensionSet.