--- packet.c.old	Tue Jun  3 07:50:51 1997
+++ packet.c	Tue Jun  3 07:51:34 1997
@@ -51,6 +51,7 @@
 #include "includes/netinet/ip.h"
 #include "includes/netinet/udp.h"
 #include "includes/netinet/if_ether.h"
+#include <net/if_arp.h>
 
 static u_int32_t checksum PROTO ((unsigned char *, int, u_int32_t));
 static u_int32_t wrapsum PROTO ((u_int32_t));
