Index: modules/book.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/book.module,v
retrieving revision 1.288
diff -u -r1.288 book.module
--- modules/book.module	4 Apr 2005 21:32:21 -0000	1.288
+++ modules/book.module	13 Apr 2005 18:15:15 -0000
@@ -55,7 +55,7 @@
 
   $links = array();
 
-  if ($type == 'node' && $node->type == 'book') {
+  if ($type == 'node' && isset($node->parent)) {
     if (!$main) {
       if (book_access('create', $node)) {
         $links[] = l(t('add child page'), "node/add/book/parent/$node->nid");