Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 136783)
+++ channels/chan_sip.c	(working copy)
@@ -2447,11 +2502,16 @@
 		} else {
 			context = global_regcontext;
 		}
-		if (onoff)
-			ast_add_extension(context, 1, ext, 1, NULL, NULL, "Noop",
-				 ast_strdup(peer->name), ast_free, "SIP");
-		else
+		if (onoff) {
+			if (!ast_exists_extension(NULL, context, ext, 1, NULL)) {
+				ast_add_extension(context, 1, ext, 1, NULL, NULL, "Noop",
+					 ast_strdup(peer->name), ast_free, "SIP");
+				if (option_verbose > 2)
+					ast_verbose(VERBOSE_PREFIX_3 "Registered SIP '%s' at %s port %d expires %d\n", peer->name, ast_inet_ntoa(peer->addr.sin_addr), ntohs(peer->addr.sin_port), expiry);
+			}
+		} else {
 			ast_context_remove_extension(context, ext, 1, NULL);
+		}
 	}
 }
 
@@ -8249,13 +8308,8 @@
 		ast_db_put("SIP/Registry", peer->name, data);
 	manager_event(EVENT_FLAG_SYSTEM, "PeerStatus", "Peer: SIP/%s\r\nPeerStatus: Registered\r\n", peer->name);
 
-	/* Is this a new IP address for us? */
-	if (inaddrcmp(&peer->addr, &oldsin)) {
-		sip_poke_peer(peer);
-		if (option_verbose > 2)
-			ast_verbose(VERBOSE_PREFIX_3 "Registered SIP '%s' at %s port %d expires %d\n", peer->name, ast_inet_ntoa(peer->addr.sin_addr), ntohs(peer->addr.sin_port), expiry);
-		register_peer_exten(peer, 1);
-	}
+	sip_poke_peer(peer);
+	register_peer_exten(peer, 1);
 	
 	/* Save User agent */
 	useragent = get_header(req, "User-Agent");