diff --git a/p4-lowlevel.el b/p4-lowlevel.el
index f1cdca7..1edd41b 100644
--- a/p4-lowlevel.el
+++ b/p4-lowlevel.el
@@ -1,4 +1,4 @@
-;;; p4-lowlwevel.el --- low-level support for Perforce operations in Emacs
+;;; p4-lowlwevel.el --- low-level support for Perforce operations in Emacs  -*- lexical-binding: t; -*-
 
 ;; Copyright (C) 2009 Magnus Henoch
 ;; Copyright (C) 2002 Curl Corporation.
diff --git a/vc-p4.el b/vc-p4.el
index 5b95f1f..77f2a7c 100644
--- a/vc-p4.el
+++ b/vc-p4.el
@@ -1,4 +1,4 @@
-;;; vc-p4.el --- Integrate Perforce support into VC mode in Emacs 21
+;;; vc-p4.el --- Integrate Perforce support into VC mode in Emacs 21  -*- lexical-binding: t; -*-
 
 ;; Copyright (C) 2009, 2010 Magnus Henoch
 ;; Copyright (C) 2002 Curl Corporation.