--- menu.module.old	2008-11-14 13:26:24.000000000 -0600
+++ menu.module	2008-11-14 14:26:30.000000000 -0600
@@ -283,7 +283,18 @@
   }
   else if ($op == 'view') {
     $data['subject'] = check_plain($menus[$delta]);
-    $data['content'] = menu_tree($delta);
+    if ($delta == 'secondary-links' && variable_get('menu_secondary_links_source', 'secondary-links') == variable_get('menu_primary_links_source', 'primary-links')) {
+      $tree = menu_tree_page_data(variable_get('menu_primary_links_source', 'primary-links'));
+      foreach ($tree as $link_data) {
+        if ($link_data['link']['in_active_trail'] && !empty($link_data['below'])) {
+          $data['content'] = menu_tree_output($link_data['below']);
+          break;
+        }
+      }
+    }
+    else {
+      $data['content'] = menu_tree($delta);
+    }
     return $data;
   }
 }