diff --git a/guestbook.install b/guestbook.install
index 642d58d..96e481c 100644
--- a/guestbook.install
+++ b/guestbook.install
@@ -37,26 +37,15 @@ function guestbook_uninstall() {
   db_delete('variable')->condition('name', 'guestbook_%', 'LIKE')->execute();
 }
 
-function guestbook_update_6001() {
-  db_drop_primary_key('guestbook');
-  db_change_field('guestbook', 'id', 'id',
-    array('type' => 'serial', 'unsigned' => TRUE, 'not null' => TRUE),
-    array('primary key' => array('id')));    
-  db_change_field('guestbook', 'anonname', 'anonname',
-    array('type' => 'varchar', 'length' => '128', 'not null' => FALSE));
-}
-
 /**
  * Rename permission "administer all guestbooks" to "moderate all guestbooks".
  */
 function guestbook_update_6200() {
-  $result = db_query("SELECT rid, perm FROM {permission} ORDER BY rid");
-  while ($role = db_fetch_object($result)) {
-    $renamed_permission = strtr($role->perm, array('administer all guestbooks' => 'moderate all guestbooks'));
-    if ($renamed_permission != $role->perm) {
-      db_query("UPDATE {permission} SET perm = '$renamed_permission' WHERE rid = " . $role->rid);
-    }
-  }
+  db_update('role_permission')
+    ->fields(array('permission' => 'moderate all guestbooks'))
+    ->condition('permission', 'administer all guestbooks')
+    ->condition('module', 'guestbook')
+    ->execute();
 }
 
 /**