diff --git a/ndhc/arp.c b/ndhc/arp.c
index 2018ffc..f0ded3a 100644
--- a/ndhc/arp.c
+++ b/ndhc/arp.c
@@ -1,5 +1,5 @@
 /* arp.c - arp ping checking
- * Time-stamp: <2011-07-06 09:18:58 njk>
+ * Time-stamp: <2011-07-06 11:39:23 njk>
  *
  * Copyright 2010-2011 Nicholas J. Kain <njkain@gmail.com>
  *
@@ -419,6 +419,11 @@ static int act_if_arp_gw_failed(struct client_state_t *cs)
     return 0;
 }
 
+void arp_set_defense_mode(struct client_state_t *cs)
+{
+    arp_switch_state(cs, AS_DEFENSE);
+}
+
 void arp_success(struct client_state_t *cs)
 {
     cs->timeout = (cs->renewTime * 1000) - (curms() - cs->leaseStartTime);
diff --git a/ndhc/arp.h b/ndhc/arp.h
index 3c8d1ab..8328392 100644
--- a/ndhc/arp.h
+++ b/ndhc/arp.h
@@ -1,5 +1,5 @@
 /* arp.h - functions to call the interface change daemon
- * Time-stamp: <2011-07-05 15:54:33 njk>
+ * Time-stamp: <2011-07-06 11:39:42 njk>
  *
  * Copyright 2010-2011 Nicholas J. Kain <njkain@gmail.com>
  *
@@ -51,6 +51,7 @@ void arp_reset_send_stats(void);
 int arp_close_fd(struct client_state_t *cs);
 int arp_check(struct client_state_t *cs, struct dhcpmsg *packet);
 int arp_gw_check(struct client_state_t *cs);
+void arp_set_defense_mode(struct client_state_t *cs);
 void arp_success(struct client_state_t *cs);
 void arp_retransmit(struct client_state_t *cs);
 void handle_arp_response(struct client_state_t *cs);
diff --git a/ndhc/state.c b/ndhc/state.c
index d7f77a9..25e9fec 100644
--- a/ndhc/state.c
+++ b/ndhc/state.c
@@ -212,6 +212,11 @@ static void an_packet(struct client_state_t *cs, struct dhcpmsg *packet,
                 log_warning("arp_check failed to make arp socket, retrying lease");
                 reinit_selecting(cs, 3000);
             }
+        } else {
+            cs->dhcpState = DS_BOUND;
+            cs->timeout = cs->renewTime * 1000;
+            arp_set_defense_mode(cs);
+            set_listen_none(cs);
         }
 
     } else if (*message == DHCPNAK) {