Index: modules/book.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/book.module,v
retrieving revision 1.406.2.1
diff -u -F^f -r1.406.2.1 book.module
--- modules/book.module	2007/02/14 04:30:33 -0000	1.406.2.1
+++ modules/book.module	2007/02/14 04:30:33 -0000
@@ -46,6 +46,12 @@ function book_access($op, $node) {
        // do nothing. node-access() will determine further access
     }
   }
+
+  if ($op == 'delete') {
+    if (user_access('edit book pages') || ($node->uid == $user->uid && user_access('edit own book pages'))) {
+      return TRUE;
+    }
+  }
 }
 
 /**