diff --git a/cogl/cogl-feature-private.c b/cogl/cogl-feature-private.c
index 070be8d0e..2f98e275a 100644
--- a/cogl/cogl-feature-private.c
+++ b/cogl/cogl-feature-private.c
@@ -84,8 +84,8 @@ _cogl_feature_check (const CoglFeatureData *data,
                                    namespace, namespace_len);
               g_string_append_c (full_extension_name, '_');
               g_string_append (full_extension_name, extension);
-              if (!cogl_check_extension (full_extension_name->str,
-                                         extensions_string))
+              if (!_cogl_check_extension (full_extension_name->str,
+                                          extensions_string))
                 break;
             }
 
diff --git a/cogl/cogl-internal.h b/cogl/cogl-internal.h
index 2645f7e87..61de4fe5a 100644
--- a/cogl/cogl-internal.h
+++ b/cogl/cogl-internal.h
@@ -98,6 +98,7 @@ const gchar *cogl_gl_error_to_string (GLenum error_code);
 #define COGL_ENABLE_BACKFACE_CULLING  (1<<5)
 
 void    _cogl_features_init (void);
+
 gint    _cogl_get_format_bpp (CoglPixelFormat format);
 
 void    cogl_enable (gulong flags);
diff --git a/cogl/cogl.c b/cogl/cogl.c
index e66f997ed..15812b924 100644
--- a/cogl/cogl.c
+++ b/cogl/cogl.c
@@ -112,6 +112,38 @@ cogl_get_proc_address (const gchar* name)
   return NULL;
 }
 
+gboolean
+_cogl_check_extension (const gchar *name, const gchar *ext)
+{
+  gchar *end;
+  gint name_len, n;
+
+  if (name == NULL || ext == NULL)
+    return FALSE;
+
+  end = (gchar*)(ext + strlen(ext));
+
+  name_len = strlen(name);
+
+  while (ext < end)
+    {
+      n = strcspn(ext, " ");
+
+      if ((name_len == n) && (!strncmp(name, ext, n)))
+	return TRUE;
+      ext += (n + 1);
+    }
+
+  return FALSE;
+}
+
+/* XXX: This has been deprecated as public API */
+gboolean
+cogl_check_extension (const char *name, const char *ext)
+{
+  return _cogl_check_extension (name, ext);
+}
+
 void
 cogl_clear (const CoglColor *color, gulong buffers)
 {
diff --git a/cogl/cogl.h b/cogl/cogl.h
index 284666ff3..1fb5567af 100644
--- a/cogl/cogl.h
+++ b/cogl/cogl.h
@@ -113,6 +113,8 @@ gboolean        cogl_features_available       (CoglFeatureFlags    features);
  */
 CoglFuncPtr     cogl_get_proc_address         (const gchar        *name);
 
+#ifndef COGL_DISABLE_DEPRECATED
+
 /**
  * cogl_check_extension:
  * @name: extension to check for
@@ -121,9 +123,15 @@ CoglFuncPtr     cogl_get_proc_address         (const gchar        *name);
  * Check whether @name occurs in list of extensions in @ext.
  *
  * Return value: %TRUE if the extension occurs in the list, %FALSE otherwize.
+ *
+ * Deprecated: 1.2: OpenGL is an implementation detail for Cogl and so it's not
+ *                  appropriate to expose OpenGL extensions through the Cogl
+ *                  API.
  */
 gboolean        cogl_check_extension          (const gchar        *name,
-                                               const gchar        *ext);
+                                               const gchar        *ext) G_GNUC_DEPRECATED;
+
+#endif /* COGL_DISABLE_DEPRECATED */
 
 /**
  * cogl_get_bitmasks:
@@ -1016,6 +1024,7 @@ typedef enum { /*< prefix=COGL_DRIVER_ERROR >*/
   COGL_DRIVER_ERROR_INVALID_VERSION
 } CoglDriverError;
 
+gboolean        _cogl_check_extension (const char *name, const char *ext);
 void            _cogl_set_indirect_context  (gboolean indirect);
 void            _cogl_set_viewport (int x, int y, int width, int height);
 gboolean        _cogl_check_driver_valid (GError **error);
diff --git a/cogl/driver/gl/cogl.c b/cogl/driver/gl/cogl.c
index 1e40c5f38..f6a3b5c41 100644
--- a/cogl/driver/gl/cogl.c
+++ b/cogl/driver/gl/cogl.c
@@ -33,31 +33,6 @@
 #include "cogl-context.h"
 #include "cogl-feature-private.h"
 
-gboolean
-cogl_check_extension (const gchar *name, const gchar *ext)
-{
-  gchar *end;
-  gint name_len, n;
-
-  if (name == NULL || ext == NULL)
-    return FALSE;
-
-  end = (gchar*)(ext + strlen(ext));
-
-  name_len = strlen(name);
-
-  while (ext < end)
-    {
-      n = strcspn(ext, " ");
-
-      if ((name_len == n) && (!strncmp(name, ext, n)))
-	return TRUE;
-      ext += (n + 1);
-    }
-
-  return FALSE;
-}
-
 #ifdef HAVE_CLUTTER_OSX
 static gboolean
 really_enable_npot (void)
@@ -142,7 +117,7 @@ _cogl_check_driver_valid (GError **error)
 
   /* OpenGL 1.2 is only supported if we have the multitexturing
      extension */
-  if (!cogl_check_extension ("GL_ARB_multitexture", gl_extensions))
+  if (!_cogl_check_extension ("GL_ARB_multitexture", gl_extensions))
     {
       g_set_error (error,
                    COGL_DRIVER_ERROR,
@@ -215,7 +190,7 @@ _cogl_features_init (void)
   gl_extensions = (const gchar*) glGetString (GL_EXTENSIONS);
 
   if (COGL_CHECK_GL_VERSION (gl_major, gl_minor, 2, 0) ||
-      cogl_check_extension ("GL_ARB_texture_non_power_of_two", gl_extensions))
+      _cogl_check_extension ("GL_ARB_texture_non_power_of_two", gl_extensions))
     {
 #ifdef HAVE_CLUTTER_OSX
       if (really_enable_npot ())
@@ -224,7 +199,7 @@ _cogl_features_init (void)
     }
 
 #ifdef GL_YCBCR_MESA
-  if (cogl_check_extension ("GL_MESA_ycbcr_texture", gl_extensions))
+  if (_cogl_check_extension ("GL_MESA_ycbcr_texture", gl_extensions))
     {
       flags |= COGL_FEATURE_TEXTURE_YUV;
     }
diff --git a/cogl/driver/gles/cogl.c b/cogl/driver/gles/cogl.c
index 21d5c268f..cc5f7c180 100644
--- a/cogl/driver/gles/cogl.c
+++ b/cogl/driver/gles/cogl.c
@@ -32,31 +32,6 @@
 #include "cogl-context.h"
 #include "cogl-feature-private.h"
 
-gboolean
-cogl_check_extension (const gchar *name, const gchar *ext)
-{
-  gchar *end;
-  gint name_len, n;
-
-  if (name == NULL || ext == NULL)
-    return FALSE;
-
-  end = (gchar*)(ext + strlen(ext));
-
-  name_len = strlen(name);
-
-  while (ext < end)
-    {
-      n = strcspn(ext, " ");
-
-      if ((name_len == n) && (!strncmp(name, ext, n)))
-	return TRUE;
-      ext += (n + 1);
-    }
-
-  return FALSE;
-}
-
 gboolean
 _cogl_check_driver_valid (GError **error)
 {