--- ppp-2.4.4.orig/pppd/ipv6cp.c	2005-08-26 01:59:34.000000000 +0200
+++ ppp-2.4.4/pppd/ipv6cp.c	2009-12-18 09:06:00.333449663 +0100
@@ -151,6 +151,7 @@
  */
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #include <netdb.h>