diff --git a/emacs/notmuch-lib.el b/emacs/notmuch-lib.el
index 8cf7261e..546ab6fd 100644
--- a/emacs/notmuch-lib.el
+++ b/emacs/notmuch-lib.el
@@ -298,7 +298,7 @@ This is basically just `format-kbd-macro' but we also convert ESC to M-."
   "Prepend cons cells describing prefix-arg ACTUAL-KEY and ACTUAL-KEY to TAIL
 
 It does not prepend if ACTUAL-KEY is already listed in TAIL."
-  (let ((key-string (concat prefix (format-kbd-macro actual-key))))
+  (let ((key-string (concat prefix (key-description actual-key))))
     ;; We don't include documentation if the key-binding is
     ;; over-ridden. Note, over-riding a binding automatically hides the
     ;; prefixed version too.
@@ -313,7 +313,7 @@ It does not prepend if ACTUAL-KEY is already listed in TAIL."
       ;; Documentation for command
       (push (cons key-string
 		  (or (and (symbolp binding) (get binding 'notmuch-doc))
-		      (notmuch-documentation-first-line binding)))
+		      (and (functionp binding) (notmuch-documentation-first-line binding))))
 	    tail)))
     tail)