diff --git a/lisp/mail/rmailedit.el b/lisp/mail/rmailedit.el
index 86e0f251f2b..c6c355a5a8a 100644
--- a/lisp/mail/rmailedit.el
+++ b/lisp/mail/rmailedit.el
@@ -28,7 +28,8 @@
 (defvar rmail-edit-map nil)
 (if rmail-edit-map
     nil
-  (setq rmail-edit-map (nconc (make-sparse-keymap) (cdr text-mode-map)))
+  ;; Make a keymap that inherits text-mode-map.
+  (setq rmail-edit-map (nconc (make-sparse-keymap) text-mode-map))
   (define-key rmail-edit-map "\C-c\C-c" 'rmail-cease-edit)
   (define-key rmail-edit-map "\C-c\C-]" 'rmail-abort-edit))