--- src/util.h.orig	2013-06-11 16:00:00.000000000 +0700
+++ src/util.h	2014-01-20 14:52:46.000000000 +0700
@@ -11,6 +11,8 @@
 #define _UTIL_H_
 
 #include "ip.h"
+#include <net/ethernet.h>
+#include <osreldate.h>
 
   /*-
    * The following macro is used to update an
@@ -98,4 +100,8 @@
   extern void     	ppp_util_ascify(char *buf, size_t max,
 			    const char *bytes, size_t len);
 
+#if (__FreeBSD_version < 700000)
+  extern char		*ether_ntoa_r(const struct ether_addr *n, char *a);
+#endif
+
 #endif
--- src/util.c.orig	2013-06-11 16:00:00.000000000 +0700
+++ src/util.c	2014-01-20 14:51:48.000000000 +0700
@@ -19,6 +19,8 @@
 #include <sys/sysctl.h>
 #include <net/route.h>
 #include <netinet/if_ether.h>
+#include <net/ethernet.h>
+#include <osreldate.h>
 
 /*
  * DEFINITIONS
@@ -1531,3 +1533,19 @@ ppp_util_ascify(char *buf, size_t bsiz, 
 	*bp = '\0';
 }
 
+#if (__FreeBSD_version < 700000)
+/*
+ * Convert a binary representation of an ethernet address to an ASCII string.
+ */
+char *
+ether_ntoa_r(const struct ether_addr *n, char *a)
+{
+        int i;
+
+        i = sprintf(a, "%02x:%02x:%02x:%02x:%02x:%02x", n->octet[0],
+            n->octet[1], n->octet[2], n->octet[3], n->octet[4], n->octet[5]);
+        if (i < 17)
+                return (NULL);
+        return (a);
+}
+#endif