--- ./channels/chan_sip.c	2014-08-08 13:01:59.000000000 +0100
+++ ./channels/chan_sip.c	2014-08-13 09:39:09.000000000 +0100
@@ -910,9 +910,12 @@
 	struct ast_str *data;	
 	/* XXX Do we need to unref socket.ser when the request goes away? */
 	struct sip_socket socket;	/*!< The socket used for this request */
+	char chan_bindhost[MAXHOSTNAMELEN];/* used to pass IP address string */
 	AST_LIST_ENTRY(sip_request) next;
 };
 
+#define MAXROUTE_TABLELEN	64
+
 /* \brief given a sip_request and an offset, return the char * that resides there
  *
  * It used to be that rlPart1, rlPart2, and the header and line arrays were character
@@ -1836,6 +1839,10 @@
 
 static struct sockaddr_in bindaddr;	/*!< UDP: The address we bind to */
 
+struct in_addr remote_addr[MAXROUTE_TABLELEN]; /*! remote addresses to search for binding */
+struct in_addr local_bindaddr[MAXROUTE_TABLELEN]; /*! corrisponding bind addresses */
+
+
 /*! \brief our (internal) default address/port to put in SIP/SDP messages
  *  internip is initialized picking a suitable address from one of the
  * interfaces, and the same port number we bind to. It is used as the
@@ -6747,7 +6754,8 @@
 		return NULL;
 	}
 
-	if (req) {
+	/* req can be null and have req->chan_bindhost */
+	if (req && req->socket.type) {
 		set_socket_transport(&p->socket, req->socket.type); /* Later in ast_sip_ouraddrfor we need this to choose the right ip and port for the specific transport */
 	} else {
 		set_socket_transport(&p->socket, SIP_TRANSPORT_UDP);
@@ -6791,7 +6799,82 @@
 	p->ocseq = INITIAL_CSEQ;
 
 	if (sip_methods[intended_method].need_rtp) {
-		p->rtp = ast_rtp_new_with_bindaddr(sched, io, 1, 0, bindaddr.sin_addr);
+		/* Leaving original asteirks code */
+
+		struct in_addr destip,chan_bindaddr;
+		chan_bindaddr.s_addr = 0;
+		char desthost[MAXHOSTNAMELEN];//store host string
+		inet_aton(desthost,&destip);
+
+		/* Calls comming in first leg else there is a call originating from this box i.e second leg */
+		if ( sin != NULL ) {
+
+			/* Source address of packet used to map to local_bindaddr addresses. This search and mapping could be */
+			/* avoided if the arrival interface of the call could be passed into this function */
+			unsigned int i=0;
+			for (i=0; i < sizeof(remote_addr) / sizeof(remote_addr[0]);i++) {
+				if ( sin->sin_addr.s_addr == remote_addr[i].s_addr ) {
+				ast_log(LOG_NOTICE, "sip_request_call ########### source matched as %s ###\n",ast_inet_ntoa(remote_addr[i]));//########## 
+				ast_log(LOG_NOTICE, "sip_request_call ########### binding locally as %s ###\n",ast_inet_ntoa(local_bindaddr[i]));//########## 
+				chan_bindaddr.s_addr = local_bindaddr[i].s_addr;
+				}
+			}	
+			ast_log(LOG_NOTICE, "sip_alloc ############## binding on %s first leg\n",ast_inet_ntoa(chan_bindaddr)); 
+
+			} else {
+
+			/* Get IP address from destination to pass to sip_alloc in the req */
+			unsigned ipbytes[4];
+			sscanf(req->chan_bindhost, "%*d@%d.%d.%d.%d:",&ipbytes[0], &ipbytes[1], &ipbytes[2], &ipbytes[3]);
+	
+			sprintf(desthost,"%d.%d.%d.%d",ipbytes[0],ipbytes[1],ipbytes[2],ipbytes[3]); 
+
+			inet_aton(desthost,&destip);
+
+			ast_log(LOG_NOTICE, "####### Hostip %d.%d.%d.%d \n",ipbytes[0],ipbytes[1],ipbytes[2],ipbytes[3]);
+		        ast_log(LOG_NOTICE, "####### chan bind host %s \n",req->chan_bindhost);
+		        //ast_log(LOG_NOTICE, "####### chan sin.sin_addr %s \n",ast_inet_ntoa(sin->sin_addr));
+		        ast_log(LOG_NOTICE, "####### destip ipaddress %s \n",ast_inet_ntoa(destip));
+			/* search for matching remote ip address destinations */
+			unsigned int i=0;
+			for (i=0; i < sizeof(remote_addr) / sizeof(remote_addr[0]);i++) {
+				if ( destip.s_addr == remote_addr[i].s_addr ) {
+		                ast_log(LOG_NOTICE, "####### destination matched as %s \n",ast_inet_ntoa(remote_addr[i]));
+		                ast_log(LOG_NOTICE, "####### binding locally as %s \n",ast_inet_ntoa(local_bindaddr[i]));
+				chan_bindaddr.s_addr = local_bindaddr[i].s_addr;
+				}
+			}	
+			
+			/* If desthost did not match maybe its a hostname */
+			if ( !chan_bindaddr.s_addr ) {
+			sscanf(req->chan_bindhost, "%*d@%*d-%s:",desthost);//our hostnames have a prefix of "X-" which is discarded to leave the real hostname.
+			ast_log(LOG_NOTICE, "####### hostname %s \n",desthost);
+			struct ast_hostent ahp;
+			struct hostent *hp;
+			hp = ast_gethostbyname(desthost,&ahp);
+				/* if the hostname did resolve */
+		               	if (hp) {
+		                destip = **(struct in_addr **)hp->h_addr_list;
+		                ast_log(LOG_NOTICE, "############ resolved ipaddress %s \n",ast_inet_ntoa(destip));
+				} else {
+					ast_log(LOG_WARNING, "Could not look up IP address of hostname.\n");
+				}
+
+				/* Search and map using the IP address having been resolved. */
+				unsigned int i=0;
+				for (i=0; i < sizeof(remote_addr) / sizeof(remote_addr[0]);i++) {
+					if ( destip.s_addr == remote_addr[i].s_addr ) {
+			                ast_log(LOG_NOTICE, "####### destination matched as %s \n",ast_inet_ntoa(remote_addr[i]));
+			                ast_log(LOG_NOTICE, "####### binding locally as %s \n",ast_inet_ntoa(local_bindaddr[i]));
+					chan_bindaddr.s_addr = local_bindaddr[i].s_addr;
+					}
+				}	
+			}
+			ast_log(LOG_NOTICE, "sip_alloc ############## binding on %s second leg \n",ast_inet_ntoa(chan_bindaddr)); 
+		}
+		
+		p->rtp = ast_rtp_new_with_bindaddr(sched, io, 1, 0, chan_bindaddr );
+		//p->rtp = ast_rtp_new_with_bindaddr(sched, io, 1, 0, bindaddr.sin_addr);
 		/* If the global videosupport flag is on, we always create a RTP interface for video */
 		if (ast_test_flag(&p->flags[1], SIP_PAGE2_VIDEOSUPPORT))
 			p->vrtp = ast_rtp_new_with_bindaddr(sched, io, 1, 0, bindaddr.sin_addr);
@@ -22177,7 +22260,14 @@
 	}
 	ast_debug(1, "Asked to create a SIP channel with formats: %s\n", ast_getformatname_multiple(tmp, sizeof(tmp), oldformat));
 
-	if (!(p = sip_alloc(NULL, NULL, 0, SIP_INVITE, NULL))) {
+
+	/* Get dest string to and pass to sip_alloc in the req */
+
+	struct sip_request *req;
+	ast_copy_string(req->chan_bindhost,dest,sizeof(tmp));
+	ast_log(LOG_NOTICE, "####### sip_request_call dest string: %s \n",req->chan_bindhost);
+
+	if (!(p = sip_alloc(NULL, NULL, 0, SIP_INVITE, req))) {
 		ast_log(LOG_ERROR, "Unable to build sip pvt data for '%s' (Out of memory or socket error)\n", dest);
 		*cause = AST_CAUSE_SWITCH_CONGESTION;
 		return NULL;
@@ -23525,9 +23615,32 @@
 	ast_clear_flag(&global_flags[1], SIP_PAGE2_IGNORESDPVERSION);
 	ast_clear_flag(&global_flags[1], SIP_PAGE2_FAX_DETECT);
 
+	unsigned i=0; /* initalise global IP address arrays */
+	for ( i=0;i < MAXROUTE_TABLELEN - 1;i++) {
+	remote_addr[i].s_addr = 0;
+	local_bindaddr[i].s_addr = 0;
+	}
 
 	/* Read the [general] config section of sip.conf (or from realtime config) */
 	for (v = ast_variable_browse(cfg, "general"); v; v = v->next) {
+		unsigned i=0;
+		char buf[MAXHOSTNAMELEN];/* Temporarily holds IP address string*/
+		for ( i=0;i < MAXROUTE_TABLELEN - 1;i++) {
+			snprintf(buf, sizeof(buf),"remoteaddr%u",i);
+			if (!memcmp(v->name, buf,strlen(buf))) {  
+			inet_aton(v->value, &remote_addr[i]);
+			ast_log(LOG_NOTICE, "Remote IP %s \n",ast_inet_ntoa(remote_addr[i]));
+			}
+		}
+
+		for ( i=0;i < MAXROUTE_TABLELEN - 1;i++) {
+		snprintf(buf, sizeof(buf),"localbindaddr%u",i);
+	        	if (!memcmp(v->name, buf,strlen(buf))) {  
+                	inet_aton(v->value, &local_bindaddr[i]);
+			ast_log(LOG_NOTICE, "Local Bind IP ip %s \n",ast_inet_ntoa(local_bindaddr[i]));
+			}
+		}
+
 		if (handle_common_options(&global_flags[0], &dummy[0], v))
 			continue;
 		if (handle_t38_options(&global_flags[0], &dummy[0], v, &global_t38_maxdatagram)) {