diff --git a/runtime/doc/todo.txt b/runtime/doc/todo.txt
index 9385b6d..da0ab92 100644
--- a/runtime/doc/todo.txt
+++ b/runtime/doc/todo.txt
@@ -33,6 +33,8 @@
 Before release 7.3:
 - Rename vim73 branch to default (hints: Xavier de Gaye, 2010 May 23)
 
+test72 causes a beep for using "u" when it doesn't work.
+
 Cursor positioning wrong with 0x200e character. (John Becket, 2010 May 6)
 
 Should readfile() ignore BOM when not in binary mode?