=== modified file 'includes/menu.inc'
--- includes/menu.inc	2009-12-17 13:10:18 +0000
+++ includes/menu.inc	2010-01-02 21:35:52 +0000
@@ -118,6 +118,11 @@ define('MENU_IS_LOCAL_TASK', 0x0080);
 define('MENU_IS_LOCAL_ACTION', 0x0100);
 
 /**
+ * Internal menu flag -- menu item is a grouping page.
+ */
+define('MENU_IS_GROUP', 0x0200);
+
+/**
  * @} End of "Menu flags".
  */
 
@@ -181,6 +186,14 @@ define('MENU_DEFAULT_LOCAL_TASK', MENU_I
 define('MENU_LOCAL_ACTION', MENU_IS_LOCAL_TASK | MENU_IS_LOCAL_ACTION | MENU_VISIBLE_IN_BREADCRUMB);
 
 /**
+ * Menu type -- a groupping page.
+ *
+ * A groupping page is only visible if there are immediate children with the
+ * same permissions.
+ */
+define('MENU_GROUP_ITEM', MENU_VISIBLE_IN_TREE | MENU_VISIBLE_IN_BREADCRUMB | MENU_IS_GROUP);
+
+/**
  * @} End of "Menu item types".
  */
 
@@ -2252,6 +2265,19 @@ function menu_rebuild() {
   list($menu, $masks) = menu_router_build();
   _menu_router_save($menu, $masks);
   _menu_navigation_links_rebuild($menu);
+  $update = db_update('menu_router');
+  $update->fields(array('access callback' => 0));
+  $update->condition('type', MENU_GROUP_ITEM);
+  $update->where('path IN (
+    SELECT m.path
+    FROM menu_router m
+    INNER JOIN menu_links ml ON ml.router_path = m.path
+    WHERE NOT EXISTS (
+      SELECT *
+      FROM menu_links ml_child
+      INNER JOIN menu_router m_child ON ml_child.router_path=m_child.path
+      WHERE ml_child.plid=ml.mlid AND m.access_callback = m_child.access_callback AND m.access_arguments = m_child.access_arguments))');
+  $update->execute();
   // Clear the menu, page and block caches.
   menu_cache_clear_all();
   _menu_clear_page_cache();