--- ../pristine/asterisk-1.2.18/channels/chan_sip.c	2007-04-30 08:36:57.000000000 -0600
+++ channels/chan_sip.c	2007-04-30 08:54:33.000000000 -0600
@@ -2492,6 +2492,7 @@
 				if (!ast_test_flag(p, SIP_CAN_BYE)) {
 					ast_set_flag(p, SIP_PENDINGBYE);
 					/* Do we need a timer here if we don't hear from them at all? */
+					sip_scheddestroy(p, 32000);
 				} else {
 					/* Send a new request: CANCEL */
 					transmit_request(p, SIP_CANCEL, p->ocseq, 1, 0);
@@ -9743,15 +9744,14 @@
 
 	switch (resp) {
 	case 100:	/* Trying */
-		if (!ignore)
+		if (!ignore && p->owner)
 			sip_cancel_destroy(p);
 		check_pendings(p);
 		ast_set_flag(p, SIP_CAN_BYE);
 		break;
 	case 180:	/* 180 Ringing */
-		if (!ignore)
-			sip_cancel_destroy(p);
 		if (!ignore && p->owner) {
+			sip_cancel_destroy(p);
 			ast_queue_control(p->owner, AST_CONTROL_RINGING);
 			if (p->owner->_state != AST_STATE_UP)
 				ast_setstate(p->owner, AST_STATE_RINGING);
@@ -9767,7 +9767,7 @@
 		check_pendings(p);
 		break;
 	case 183:	/* Session progress */
-		if (!ignore)
+		if (!ignore && p->owner)
 			sip_cancel_destroy(p);
 		/* Ignore 183 Session progress without SDP */
 		if (find_sdp(req)) {
@@ -9781,7 +9781,7 @@
 		check_pendings(p);
 		break;
 	case 200:	/* 200 OK on invite - someone's answering our call */
-		if (!ignore)
+		if (!ignore && p->owner)
 			sip_cancel_destroy(p);
 		p->authtries = 0;
 		if (find_sdp(req)) {
@@ -9870,6 +9870,7 @@
 			ast_queue_hangup(p->owner);
 		else if (!ignore)
 			update_call_counter(p, DEC_CALL_LIMIT);
+		sip_scheddestroy(p, 32000);
 		break;
 	case 491: /* Pending */
 		/* we have to wait a while, then retransmit */
@@ -10261,7 +10262,7 @@
 					ast_set_flag(p, SIP_NEEDDESTROY);	
 			} else if ((resp >= 100) && (resp < 200)) {
 				if (sipmethod == SIP_INVITE) {
-					if (!ignore)
+					if (!ignore && p->owner)
 						sip_cancel_destroy(p);
 					if (find_sdp(req))
 						process_sdp(p, req);
@@ -10325,7 +10326,7 @@
 			break;
 		default:	/* Errors without handlers */
 			if ((resp >= 100) && (resp < 200)) {
-				if (sipmethod == SIP_INVITE && !ignore) 	/* re-invite */
+				if (sipmethod == SIP_INVITE && !ignore && p->owner) 	/* re-invite */
 					sip_cancel_destroy(p);
 				
 			}
@@ -10339,7 +10340,7 @@
 				case 503: /* Service Unavailable */
 				case 504: /* Server timeout */
 
-					if (sipmethod == SIP_INVITE && !ignore) {	/* re-invite failed */
+					if (sipmethod == SIP_INVITE && !ignore && p->owner) {	/* re-invite failed */
 						sip_cancel_destroy(p);
 					}
 					break;
@@ -10617,7 +10618,8 @@
 		/* Use this as the basis */
 		if (debug)
 			ast_verbose("Using INVITE request as basis request - %s\n", p->callid);
-		sip_cancel_destroy(p);
+		if(p->owner)
+			sip_cancel_destroy(p);
 		/* This call is no longer outgoing if it ever was */
 		ast_clear_flag(p, SIP_OUTGOING);
 		/* This also counts as a pending invite */