--- asterisk-1.8-1.8.9.3-rev-356570/channels/chan_sip.c	2012-03-05 09:59:26.000000000 +0100
+++ asterisk-new/channels/chan_sip.c	2012-03-05 10:06:27.000000000 +0100
@@ -12789,7 +12789,7 @@
 	if (p->owner->_state == AST_STATE_UP || ast_test_flag(&p->flags[0], SIP_OUTGOING)) {
 		struct sip_request req;
 
-		if (p->invitestate == INV_CONFIRMED || p->invitestate == INV_TERMINATED) {
+		if ((p->invitestate == INV_CONFIRMED || p->invitestate == INV_TERMINATED) && !p->pendinginvite) {
 			reqprep(&req, p, ast_test_flag(&p->flags[0], SIP_REINVITE_UPDATE) ? SIP_UPDATE : SIP_INVITE, 0, 1);
 
 			add_header(&req, "Allow", ALLOWED_METHODS);