diff -Naru arpwatch-2.1a15.orig/arpwatch.8 arpwatch-2.1a15/arpwatch.8
--- arpwatch-2.1a15.orig/arpwatch.8	2006-09-22 19:33:49.000000000 +0400
+++ arpwatch-2.1a15/arpwatch.8	2006-09-22 19:34:52.000000000 +0400
@@ -59,6 +59,11 @@
 .B -s
 .I sendmail_path
 ]
+.br
+.ti +8
+[
+.B -p
+]
 .ad
 .SH DESCRIPTION
 .B Arpwatch
@@ -116,6 +121,15 @@
 useful for redirecting reports to log files instead of mail. (This feature
 comes from Debian).
 .LP
+The
+.B -p
+flag disables promiscuous operation. ARP broadcasts get through hubs without
+having the interface in promiscuous mode, while saving considerable resources
+that would be wasted on processing gigabytes of non-broadcast traffic. OTOH,
+setting promiscuous mode does not mean getting 100% traffic that would concern
+.B arpwatch.
+YMMV. (This feature comes from Debian).
+.LP
 Note that an empty
 .I arp.dat
 file must be created before the first time you run
diff -Naru arpwatch-2.1a15.orig/arpwatch.c arpwatch-2.1a15/arpwatch.c
--- arpwatch-2.1a15.orig/arpwatch.c	2006-09-22 19:33:49.000000000 +0400
+++ arpwatch-2.1a15/arpwatch.c	2006-09-22 19:34:07.000000000 +0400
@@ -162,6 +162,7 @@
 		"N"
 		"r:"
 		"s:"
+		"p"
 	;
 
 	if (argv[0] == NULL)
@@ -216,6 +217,10 @@
 			path_sendmail = optarg;
 			break;
 
+		case 'p':
+			++nopromisc;
+			break;
+
 		default:
 			usage();
 		}
@@ -283,7 +288,7 @@
 		snaplen = max(sizeof(struct ether_header),
 		    sizeof(struct fddi_header)) + sizeof(struct ether_arp);
 		timeout = 1000;
-		pd = pcap_open_live(interface, snaplen, 1, timeout, errbuf);
+		pd = pcap_open_live(interface, snaplen, !nopromisc, timeout, errbuf);
 		if (pd == NULL) {
 			syslog(LOG_ERR, "pcap open %s: %s", interface, errbuf);
 			exit(1);
@@ -769,6 +774,7 @@
 		"[-n net[/width]] "
 		"[-r file] "
 		"[-s sendmail_path] "
+		"[-p] "
 		"\n"
 	;
 
diff -Naru arpwatch-2.1a15.orig/util.c arpwatch-2.1a15/util.c
--- arpwatch-2.1a15.orig/util.c	2004-01-23 01:25:39.000000000 +0300
+++ arpwatch-2.1a15/util.c	2006-09-22 19:35:15.000000000 +0400
@@ -61,6 +61,7 @@
 
 int debug = 0;
 int initializing = 1;			/* true if initializing */
+int nopromisc = 0;			/* don't activate promisc mode by default */
 
 /* syslog() helper routine */
 void
diff -Naru arpwatch-2.1a15.orig/util.h arpwatch-2.1a15/util.h
--- arpwatch-2.1a15.orig/util.h	1996-10-06 14:22:14.000000000 +0400
+++ arpwatch-2.1a15/util.h	2006-09-22 19:34:07.000000000 +0400
@@ -17,3 +17,4 @@
 
 extern int debug;
 extern int initializing;
+extern int nopromisc;