--- do_conversion.c.orig	Mon Aug 23 07:50:25 2010
+++ do_conversion.c	Mon Aug 23 07:50:46 2010
@@ -292,6 +292,7 @@ modification follow.
 
 
 #include <string.h>
+#include <ctype.h>
 #include "periodic.h"
 
 struct CONVERTS{
