Index: modules/book/book.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/book/book.module,v
retrieving revision 1.546
diff -u -p -r1.546 book.module
--- modules/book/book.module	26 Jun 2010 12:42:47 -0000	1.546
+++ modules/book/book.module	2 Jul 2010 14:12:48 -0000
@@ -457,7 +457,7 @@ function _book_parent_select($book_link)
   $form = array(
     '#type' => 'hidden',
     '#value' => -1,
-    '#prefix' => '<div id="edit-book-plid-wrapper">',
+    '#prefix' => '<div id="edit-book-plid-form-wrapper">',
     '#suffix' => '</div>',
   );
 
@@ -481,6 +481,8 @@ function _book_parent_select($book_link)
       '#description' => t('The parent page in the book. The maximum depth for a book and all child pages is !maxdepth. Some pages in the selected book may not be available as parents if selecting them would exceed this limit.', array('!maxdepth' => MENU_MAX_DEPTH)),
       '#options' => book_toc($book_link['bid'], $book_link['parent_depth_limit'], array($book_link['mlid'])),
       '#attributes' => array('class' => array('book-title-select')),
+      '#prefix' => $form['#prefix'],
+      '#suffix' => $form['#suffix'],
     );
   }
 
@@ -558,7 +560,7 @@ function _book_add_form_elements(&$form,
     '#attributes' => array('class' => array('book-title-select')),
     '#ajax' => array(
       'path' => 'book/js/form',
-      'wrapper' => 'edit-book-plid-wrapper',
+      'wrapper' => 'edit-book-plid-form-wrapper',
       'effect' => 'fade',
       'speed' => 'fast',
     ),