--- arpwatch.h.orig	Mon Apr 27 19:41:46 1998
+++ arpwatch.h	Mon Apr 27 19:42:16 1998
@@ -3,7 +3,9 @@
 #define NEWARPFILE "arp.dat.new"
 #define ARPFILE "arp.dat"
 #define OLDARPFILE "arp.dat-"
+#ifndef ETHERCODES
 #define ETHERCODES "ethercodes.dat"
+#endif
 #define CHECKPOINT (15*60)		/* Checkpoint time in seconds */
 
 #define MEMCMP(a, b, n) memcmp((char *)a, (char *)b, n)