--- docs/manual/rewrite/flags.xml	(revision 1729409)
+++ docs/manual/rewrite/flags.xml	(working copy)
@@ -658,6 +658,8 @@ 
 URI in request' warnings.
 </p>
 
+<p>Note: It is possible that newly created status codes are not yet recognized by HTTPD. Using an unrecognized status code will result in a 500 error and error log message.</p>
+
 </section>
 
 <section id="flag_s"><title>S|skip</title>