diff --git a/src/ChangeLog b/src/ChangeLog
index c9196c5b707..b11ea0fa02c 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,8 @@
 2004-11-25  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+	* keyboard.c (command_loop_1): Print a message describing the key
+	the user just pressed when this key has no binding.
+
 	* sysdep.c (sys_signal): Don't use SA_RESTART if SYNC_INPUT is set.
 	(emacs_open, emacs_read, emacs_write): Check QUIT when interrupted.
 
diff --git a/src/keyboard.c b/src/keyboard.c
index 59dc6e214e5..d96879a453f 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -1618,7 +1618,10 @@ command_loop_1 ()
       if (NILP (Vthis_command))
 	{
 	  /* nil means key is undefined.  */
+	  Lisp_Object keys = Fvector (i, keybuf);
+	  keys = Fkey_description (keys, Qnil);
 	  bitch_at_user ();
+	  message_with_string ("%s is undefined", keys, 0);
 	  current_kboard->defining_kbd_macro = Qnil;
 	  update_mode_lines = 1;
 	  current_kboard->Vprefix_arg = Qnil;