diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 379a1ec9f7d..7304c180115 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-06-27  Stephen Berman  <stephen.berman@gmx.net>
+
+	* obsolete/otodo-mode.el: Add obsolescence info to file header.
+
 2013-06-27  Leo Liu  <sdl.web@gmail.com>
 
 	* net/eww.el (eww-read-bookmarks): Check file size.
diff --git a/lisp/obsolete/otodo-mode.el b/lisp/obsolete/otodo-mode.el
index c109ecefb7d..c3a4b082be3 100644
--- a/lisp/obsolete/otodo-mode.el
+++ b/lisp/obsolete/otodo-mode.el
@@ -6,6 +6,7 @@
 ;; Maintainer: Stephen Berman <stephen.berman@gmx.net>
 ;; Created: 2 Aug 1997
 ;; Keywords: calendar, todo
+;; Obsolete-since: 24.4
 
 ;; This file is part of GNU Emacs.