=== modified file 'modules/node/node.module'
--- modules/node/node.module	2010-07-16 02:37:05 +0000
+++ modules/node/node.module	2010-07-24 07:19:47 +0000
@@ -1256,6 +1256,8 @@ function node_view($node, $view_mode = '
 function node_build_content($node, $view_mode = 'full') {
   // Remove previously built content, if exists.
   $node->content = array();
+  // A node must know what is presented by its view_mode.
+  $node->view_mode = $view_mode;
 
   // The 'view' hook can be implemented to overwrite the default function
   // to display nodes.
@@ -1321,7 +1323,7 @@ function node_show($node, $message = FAL
  */
 function node_is_page($node) {
   $page_node = menu_get_object();
-  return (!empty($page_node) ? $page_node->nid == $node->nid : FALSE);
+  return !empty($page_node) && $page_node->nid == $node->nid && $node->view_mode == 'full';
 }
 
 /**