diff --git a/src/mod/endpoints/mod_sofia/mod_sofia.c b/src/mod/endpoints/mod_sofia/mod_sofia.c
index c574077d64..ea30b7b924 100644
--- a/src/mod/endpoints/mod_sofia/mod_sofia.c
+++ b/src/mod/endpoints/mod_sofia/mod_sofia.c
@@ -985,22 +985,12 @@ static switch_status_t sofia_receive_message(switch_core_session_t *session, swi
 			if (code == 407 && !msg->numeric_arg) {
 				const char *to_uri = switch_channel_get_variable(channel, "sip_to_uri");
 				const char *to_host = reason;
-				const char *val;
-				const char *sticky = NULL;
-				
-				if (switch_test_flag(tech_pvt, TFLAG_NAT) ||
-					(val = switch_channel_get_variable(channel, "sip-force-contact")) || 
-					((val = switch_channel_get_variable(channel, "sip_sticky_contact")) && switch_true(val))) {
-					sticky = tech_pvt->record_route;
-					switch_channel_set_variable(channel, "sip_nat_detected", "true");
-				}
-
 
 				if (switch_strlen_zero(to_host)) {
 					to_host = switch_channel_get_variable(channel, "sip_to_host");
 				}
 				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Challenging call %s\n", to_uri);
-				sofia_reg_auth_challange(NULL, tech_pvt->profile, tech_pvt->nh, REG_INVITE, to_host, 0, sticky); 
+				sofia_reg_auth_challange(NULL, tech_pvt->profile, tech_pvt->nh, REG_INVITE, to_host, 0, NULL); 
 				switch_channel_hangup(channel, SWITCH_CAUSE_USER_CHALLENGE);
 			} else if (code == 484 && msg->numeric_arg) {
 				const char *to = switch_channel_get_variable(channel, "sip_to_uri");
diff --git a/src/mod/endpoints/mod_sofia/mod_sofia.h b/src/mod/endpoints/mod_sofia/mod_sofia.h
index 76ccc0d608..70fd208c1c 100644
--- a/src/mod/endpoints/mod_sofia/mod_sofia.h
+++ b/src/mod/endpoints/mod_sofia/mod_sofia.h
@@ -518,7 +518,7 @@ void sofia_presence_event_handler(switch_event_t *event);
 void sofia_presence_mwi_event_handler(switch_event_t *event);
 void sofia_presence_cancel(void);
 switch_status_t config_sofia(int reload, char *profile_name);
-void sofia_reg_auth_challange(nua_t *nua, sofia_profile_t *profile, nua_handle_t *nh, sofia_regtype_t regtype, const char *realm, int stale, const char *sticky);
+void sofia_reg_auth_challange(nua_t *nua, sofia_profile_t *profile, nua_handle_t *nh, sofia_regtype_t regtype, const char *realm, int stale, const char *new_via);
 auth_res_t sofia_reg_parse_auth(sofia_profile_t *profile, sip_authorization_t const *authorization, sip_t const *sip, const char *regstr, 
 								char *np, size_t nplen, char *ip, switch_event_t **v_event, long exptime, sofia_regtype_t regtype, const char *to_user);
 
@@ -555,7 +555,7 @@ int sofia_glue_get_user_host(char *in, char **user, char **host);
 switch_call_cause_t sofia_glue_sip_cause_to_freeswitch(int status);
 void sofia_glue_do_xfer_invite(switch_core_session_t *session);
 uint8_t sofia_reg_handle_register(nua_t *nua, sofia_profile_t *profile, nua_handle_t *nh, sip_t const *sip, 
-								  sofia_regtype_t regtype, char *key, uint32_t keylen, switch_event_t **v_event, const char *sticky);
+								  sofia_regtype_t regtype, char *key, uint32_t keylen, switch_event_t **v_event, const char *new_via);
 extern switch_endpoint_interface_t *sofia_endpoint_interface;
 void sofia_presence_set_chat_hash(private_object_t *tech_pvt, sip_t const *sip);
 switch_status_t sofia_on_hangup(switch_core_session_t *session);
@@ -634,3 +634,4 @@ void sofia_glue_tech_patch_sdp(private_object_t *tech_pvt);
 switch_status_t sofia_glue_tech_proxy_remote_addr(private_object_t *tech_pvt);
 void sofia_presence_event_thread_start(void);
 void sofia_reg_expire_call_id(sofia_profile_t *profile, const char *call_id);
+char *sofia_glue_hack_via(sofia_profile_t *profile, sip_t const *sip, int network_port);
diff --git a/src/mod/endpoints/mod_sofia/sofia_glue.c b/src/mod/endpoints/mod_sofia/sofia_glue.c
index 54d2854061..769e133ec2 100644
--- a/src/mod/endpoints/mod_sofia/sofia_glue.c
+++ b/src/mod/endpoints/mod_sofia/sofia_glue.c
@@ -463,6 +463,32 @@ switch_status_t sofia_glue_ext_address_lookup(char **ip, switch_port_t *port, ch
 }
 
 
+char *sofia_glue_hack_via(sofia_profile_t *profile, sip_t const *sip, int network_port)
+{
+	
+	char *full_via, *p, *new_via = NULL;
+
+	if (sip->sip_via) {
+		full_via = sip_header_as_string(profile->home, (void *) sip->sip_via);
+		if ((p = (char *)switch_stristr("rport=", full_via))) {
+			*p = '\0';
+			p--;
+		}
+		
+		p = end_of_p(full_via);
+		if (*p == ';') {
+			*p = '\0';
+		}
+
+	
+		new_via = switch_mprintf("%s;rport=%d", full_via, network_port);
+		su_free(profile->home, full_via);
+	}
+
+	return new_via;
+}
+
+
 const char *sofia_glue_get_unknown_header(sip_t const *sip, const char *name)
 {
 	sip_unknown_t *un;
diff --git a/src/mod/endpoints/mod_sofia/sofia_reg.c b/src/mod/endpoints/mod_sofia/sofia_reg.c
index aba7935d82..ac22e7e0d1 100644
--- a/src/mod/endpoints/mod_sofia/sofia_reg.c
+++ b/src/mod/endpoints/mod_sofia/sofia_reg.c
@@ -381,7 +381,7 @@ char *sofia_reg_find_reg_url(sofia_profile_t *profile, const char *user, const c
 }
 
 
-void sofia_reg_auth_challange(nua_t *nua, sofia_profile_t *profile, nua_handle_t *nh, sofia_regtype_t regtype, const char *realm, int stale, const char *sticky)
+void sofia_reg_auth_challange(nua_t *nua, sofia_profile_t *profile, nua_handle_t *nh, sofia_regtype_t regtype, const char *realm, int stale, const char *new_via)
 {
 	switch_uuid_t uuid;
 	char uuid_str[SWITCH_UUID_FORMATTED_LENGTH + 1];
@@ -403,12 +403,12 @@ void sofia_reg_auth_challange(nua_t *nua, sofia_profile_t *profile, nua_handle_t
 	if (regtype == REG_REGISTER) {
 		nua_respond(nh, 
 					SIP_401_UNAUTHORIZED, 
-					TAG_IF(sticky, NUTAG_PROXY(sticky)),
+					TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 					TAG_IF(nua, NUTAG_WITH_THIS(nua)), SIPTAG_WWW_AUTHENTICATE_STR(auth_str), TAG_END());
 	} else if (regtype == REG_INVITE) {
 		nua_respond(nh, 
 					SIP_407_PROXY_AUTH_REQUIRED, 
-					TAG_IF(sticky, NUTAG_PROXY(sticky)),
+					TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 					TAG_IF(nua, NUTAG_WITH_THIS(nua)), SIPTAG_PROXY_AUTHENTICATE_STR(auth_str), TAG_END());
 	}
 
@@ -416,7 +416,7 @@ void sofia_reg_auth_challange(nua_t *nua, sofia_profile_t *profile, nua_handle_t
 }
 
 uint8_t sofia_reg_handle_register(nua_t * nua, sofia_profile_t *profile, nua_handle_t * nh, sip_t const *sip, sofia_regtype_t regtype, char *key,
-								  uint32_t keylen, switch_event_t **v_event, const char *sticky)
+								  uint32_t keylen, switch_event_t **v_event, const char *new_via)
 {
 	sip_to_t const *to = NULL;
 	sip_expires_t const *expires = NULL;
@@ -567,12 +567,12 @@ uint8_t sofia_reg_handle_register(nua_t * nua, sofia_profile_t *profile, nua_han
 			if (auth_res == AUTH_FORBIDDEN) {
 				nua_respond(nh, 
 							SIP_403_FORBIDDEN, 
-							TAG_IF(sticky, NUTAG_PROXY(sticky)),							
+							TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),							
 							NUTAG_WITH_THIS(nua), TAG_END());
 			} else {
 				nua_respond(nh, 
 							SIP_401_UNAUTHORIZED, 
-							TAG_IF(sticky, NUTAG_PROXY(sticky)),
+							TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 							NUTAG_WITH_THIS(nua), TAG_END());
 			}
 			return 1;
@@ -580,7 +580,7 @@ uint8_t sofia_reg_handle_register(nua_t * nua, sofia_profile_t *profile, nua_han
 	}
 
 	if (!authorization || stale) {
-		sofia_reg_auth_challange(nua, profile, nh, regtype, to_host, stale, sticky);
+		sofia_reg_auth_challange(nua, profile, nh, regtype, to_host, stale, new_via);
 		if (regtype == REG_REGISTER && profile->debug) {
 			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Requesting Registration from: [%s@%s]\n", to_user, to_host);
 		}
@@ -711,7 +711,7 @@ uint8_t sofia_reg_handle_register(nua_t * nua, sofia_profile_t *profile, nua_han
 			}
 			nua_respond(nh, 
 						SIP_200_OK, 
-						TAG_IF(sticky, NUTAG_PROXY(sticky)),						
+						TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),						
 						SIPTAG_CONTACT_STR(new_contact), NUTAG_WITH_THIS(nua), TAG_END());
 			switch_safe_free(new_contact);
 			if (switch_event_create(&event, SWITCH_EVENT_MESSAGE_QUERY) == SWITCH_STATUS_SUCCESS) {
@@ -722,7 +722,7 @@ uint8_t sofia_reg_handle_register(nua_t * nua, sofia_profile_t *profile, nua_han
 		} else {
 			nua_respond(nh, 
 						SIP_200_OK, 
-						TAG_IF(sticky, NUTAG_PROXY(sticky)),
+						TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 						SIPTAG_CONTACT(contact), NUTAG_WITH_THIS(nua), TAG_END());
 			
 			if (switch_event_create_subclass(&s_event, SWITCH_EVENT_CUSTOM, MY_EVENT_UNREGISTER) == SWITCH_STATUS_SUCCESS) {
@@ -752,7 +752,7 @@ void sofia_reg_handle_sip_i_register(nua_t * nua, sofia_profile_t *profile, nua_
 	char network_ip[80];
 	su_addrinfo_t *my_addrinfo = msg_addrinfo(nua_current_request(nua));
 	sofia_regtype_t type = REG_REGISTER;
-	char *sticky = NULL;
+	char *new_via = NULL;
 	int network_port = 0;
 
 	get_addr(network_ip, sizeof(network_ip), &((struct sockaddr_in *) my_addrinfo->ai_addr)->sin_addr);
@@ -784,8 +784,10 @@ void sofia_reg_handle_sip_i_register(nua_t * nua, sofia_profile_t *profile, nua_
 			}
 			
 			if (ok) {
-				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Setting NAT mode based on acl %s\n", last_acl);
-				sticky = switch_mprintf("sip:%s@%s:%d", sip->sip_contact->m_url->url_user, network_ip, network_port);
+				if (sip->sip_via) {
+					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Setting NAT mode based on acl %s\n", last_acl);
+					new_via = sofia_glue_hack_via(profile, sip, network_port);
+				}
 			}
 		}
 	}
@@ -794,7 +796,7 @@ void sofia_reg_handle_sip_i_register(nua_t * nua, sofia_profile_t *profile, nua_
 	if (!(profile->mflags & MFLAG_REGISTER)) {
 		nua_respond(nh, 
 					SIP_403_FORBIDDEN, 
-					TAG_IF(sticky, NUTAG_PROXY(sticky)),
+					TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 					NUTAG_WITH_THIS(nua), TAG_END());
 		goto end;
 	}
@@ -817,7 +819,7 @@ void sofia_reg_handle_sip_i_register(nua_t * nua, sofia_profile_t *profile, nua_
 			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "IP %s Rejected by acl %s\n", network_ip,  profile->reg_acl[x]);
 			nua_respond(nh, 
 						SIP_403_FORBIDDEN, 
-						TAG_IF(sticky, NUTAG_PROXY(sticky)),
+						TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 						NUTAG_WITH_THIS(nua), TAG_END());
 			goto end;
 		}
@@ -827,12 +829,12 @@ void sofia_reg_handle_sip_i_register(nua_t * nua, sofia_profile_t *profile, nua_
 		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Received an invalid packet!\n");
 		nua_respond(nh, 
 					SIP_500_INTERNAL_SERVER_ERROR, 
-					TAG_IF(sticky, NUTAG_PROXY(sticky)),
+					TAG_IF(new_via, SIPTAG_VIA((void *)-1)), TAG_IF(new_via, SIPTAG_VIA_STR(new_via)),
 					TAG_END());
 		goto end;
 	}
 
-	sofia_reg_handle_register(nua, profile, nh, sip, type, key, sizeof(key), &v_event, sticky);
+	sofia_reg_handle_register(nua, profile, nh, sip, type, key, sizeof(key), &v_event, new_via);
 
 	if (v_event) {
 		switch_event_fire(&v_event);
@@ -840,7 +842,7 @@ void sofia_reg_handle_sip_i_register(nua_t * nua, sofia_profile_t *profile, nua_
 
  end:	
 
-	switch_safe_free(sticky);
+	switch_safe_free(new_via);
 	nua_handle_destroy(nh);
 
 }