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Index: modules/book.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/book.module,v
retrieving revision 1.283
diff -u -F^function -r1.283 book.module
--- modules/book.module	30 Jan 2005 08:53:05 -0000	1.283
+++ modules/book.module	31 Jan 2005 02:35:11 -0000
@@ -39,7 +39,12 @@ function book_access($op, $node) {
     // of that page waiting for approval.  That is, only updates that
     // don't overwrite the current or pending information are allowed.
 
-    return ((user_access('maintain books') && !$node->moderate) || ($node->uid == $user->uid && user_access('edit own book pages')));
+    if ((user_access('maintain books') && !$node->moderate) || ($node->uid == $user->uid && user_access('edit own book pages'))) {
+      // do nothing. node-access() will determine further access
+    }
+    else {
+      return FALSE;
+    }
   }
 }