diff --git a/tmux.h b/tmux.h
index 06756001..a1b84433 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tmux.h,v 1.6 2009/06/04 18:48:24 nicm Exp $ */
+/* $OpenBSD: tmux.h,v 1.7 2009/06/24 05:35:07 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -1642,7 +1642,7 @@ int		 session_last(struct session *);
 
 /* utf8.c */
 void	utf8_build(void);
-int	utf8_width(u_char *);
+int	utf8_width(const u_char *);
 
 /* util.c */
 char   *section_string(char *, size_t, size_t, size_t);
diff --git a/utf8.c b/utf8.c
index 30f9b6e5..268d8e57 100644
--- a/utf8.c
+++ b/utf8.c
@@ -1,4 +1,4 @@
-/* $Id: utf8.c,v 1.6 2009-05-04 17:58:27 nicm Exp $ */
+/* $OpenBSD: utf8.c,v 1.2 2009/06/24 05:35:07 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -297,7 +297,7 @@ utf8_split(u_int uvalue, u_char *data)
 }
 
 int
-utf8_width(u_char *udata)
+utf8_width(const u_char *udata)
 {
 	struct utf8_width_entry	*item;
 	u_int			 uvalue;