$NetBSD$

--- src/gcalctool.c.orig	2010-11-16 22:44:48.000000000 +0000
+++ src/gcalctool.c
@@ -20,6 +20,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <locale.h>
 
 #include "currency.h"
 #include "unittest.h"
