Index: channels/chan_sip.c
===================================================================
RCS file: /usr/cvsroot/asterisk/channels/chan_sip.c,v
retrieving revision 1.864
diff -u -r1.864 chan_sip.c
--- channels/chan_sip.c	26 Sep 2005 03:05:37 -0000	1.864
+++ channels/chan_sip.c	28 Sep 2005 22:20:21 -0000
@@ -22,6 +22,7 @@
  * 
  */
 
+#define PATCH_5215
 
 #include <stdio.h>
 #include <ctype.h>
@@ -10445,7 +10446,12 @@
 		} else if (p->ocseq && (p->ocseq < seqno)) {
 			ast_log(LOG_DEBUG, "Ignoring out of order response %d (expecting %d)\n", seqno, p->ocseq);
 			return -1;
+#ifndef PATCH_5215
 		} else if (p->ocseq && (p->ocseq != seqno)) {
+#else
+		} else if ((p->ocseq && (p->ocseq != seqno))
+			   && !(ast_test_flag(p, SIP_OUTGOING) && p->pendinginvite && (p->pendinginvite == seqno))) {
+#endif
 			/* ignore means "don't do anything with it" but still have to 
 			   respond appropriately  */
 			ignore=1;
@@ -10468,7 +10474,12 @@
 	if (option_debug > 2)
 		ast_log(LOG_DEBUG, "**** Received %s (%d) - Command in SIP %s\n", sip_methods[p->method].text, sip_methods[p->method].id, cmd); 
 
+#ifndef PATCH_5215
 	if (p->icseq && (p->icseq > seqno)) {
+#else
+	if ((p->icseq && (p->icseq > seqno))
+	    && !(!ast_test_flag(p, SIP_OUTGOING) && (req->method == SIP_ACK) && p->pendinginvite && (p->pendinginvite == seqno))) {
+#endif
 		ast_log(LOG_DEBUG, "Ignoring too old SIP packet packet %d (expecting >= %d)\n", seqno, p->icseq);
 		return -1;
 	} else if (p->icseq && (p->icseq == seqno) && req->method != SIP_ACK &&(p->method != SIP_CANCEL|| ast_test_flag(p, SIP_ALREADYGONE))) {