diff -Naur asterisk-1.6.1.6.orig/channels/chan_sip.c asterisk-1.6.1.6/channels/chan_sip.c
--- asterisk-1.6.1.6.orig/channels/chan_sip.c	2009-08-10 23:30:55.000000000 +0400
+++ asterisk-1.6.1.6/channels/chan_sip.c	2009-12-02 23:27:20.000000000 +0300
@@ -3283,14 +3283,9 @@
 	/* If there are packets still waiting for delivery, delay the destruction */
 	if (p->packets) {
 		if (!p->needdestroy) {
-			char method_str[31];
 			ast_debug(3, "Re-scheduled destruction of SIP call %s\n", p->callid ? p->callid : "<unknown>");
 			append_history(p, "ReliableXmit", "timeout");
-			if (sscanf(p->lastmsg, "Tx: %30s", method_str) == 1 || sscanf(p->lastmsg, "Rx: %30s", method_str) == 1) {
-				if (method_match(SIP_CANCEL, method_str) || method_match(SIP_BYE, method_str)) {
-					p->needdestroy = 1;
-				}
-			}
+			p->needdestroy = 1;
 			return 10000;
 		} else {
 			/* They've had their chance to respond. Time to bail */