$NetBSD: patch-ab,v 1.11 2013/08/16 02:04:25 obache Exp $

--- src/threads.h.orig	2011-09-20 18:42:48.000000000 +0000
+++ src/threads.h
@@ -23,6 +23,7 @@
 #define __THREADS_H__
 
 #include <unistd.h>
+#include <pthread.h>
 
 /*  allocated in main.c */
 extern pthread_mutex_t checking_mail_lock;