diff -uNr cabocha-0.53-original/src/common.h cabocha-0.53/src/common.h
--- cabocha-0.53-original/src/common.h	2005-12-24 21:30:35.000000000 +0900
+++ cabocha-0.53/src/common.h	2008-05-25 19:13:12.000000000 +0900
@@ -32,6 +32,8 @@
 #define COPYRIGHT "CaboCha (Yet Another Japanese Dependency Structure Analyzer)\n\
 Copyright (C) 2001-2004 Taku Kudo, All rights reserved.\n"
 
+#include <string.h>
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif