--- asterisk/channels/chan_sip.c.original	2013-12-02 17:05:13.081705846 +0400
+++ asterisk/channels/chan_sip.c	2013-12-03 11:08:02.838456070 +0400
@@ -4121,6 +4121,18 @@
 				pkt->timer_a = 2 ;
 			} else {
 				pkt->timer_a = 2 * pkt->timer_a;
+
+				ast_log(LOG_WARNING, "SIP retransmission limit reached pkt=0x%lx #%d (%d) %s - %d (timer_t1=%d, timer_a=%d)\n",
+					(unsigned long)pkt,
+					pkt->retransid,
+					pkt->retrans,
+					sip_methods[pkt->method].text,
+					pkt->method,
+					pkt->timer_t1,
+					pkt->timer_a);
+
+				pkt->retrans_stop = 1;
+				pkt->is_fatal = 1;
 			}
 
 			/* For non-invites, a maximum of 4 secs */