--- Wnn/jserver/do_env.c.orig
+++ Wnn/jserver/do_env.c
@@ -49,6 +49,7 @@
 /*	Version 4.0
  */
 #include <stdio.h>
+#include <string.h>
 
 #include "demcom.h"
 #include "commonhd.h"
