Index: modules/node/node.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/node/node.module,v
retrieving revision 1.1337
diff -u -p -r1.1337 node.module
--- modules/node/node.module	18 Jan 2011 18:52:31 -0000	1.1337
+++ modules/node/node.module	5 Feb 2011 07:06:34 -0000
@@ -483,6 +483,10 @@ function node_type_load($name) {
 /**
  * Saves a node type to the database.
  *
+ * If you are manually modifying a node type ensure that you set the modified
+ * property to TRUE otherwise the changes will be stored in the database, but
+ * ignored by the API.
+ *
  * @param $info
  *   The node type to save, as an object.
  *