From 2494fa613ba4fd1eb0cdbea7b8c05e43f84f890f Mon Sep 17 00:00:00 2001
From: Joshua Colp <jcolp@digium.com>
Date: Tue, 10 Jun 2008 14:12:51 +0000
Subject: [PATCH] git-svn-id:
 https://origsvn.digium.com/svn/asterisk/branches/1.6.0@121505
 65c4cc65-6c06-0410-ace0-fbb531ad65f3

---
 channels/chan_sip.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index a092b2790e..54d9cba2a9 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -7473,8 +7473,13 @@ static int reqprep(struct sip_request *req, struct sip_pvt *p, int sipmethod, in
 		ast_string_field_set(p, url, NULL);
 	}
 
-	/* Add Session-Timers related headers if the feature is active for this session */
-	if (p->stimer && p->stimer->st_active == TRUE && p->stimer->st_active_peer_ua == TRUE) {
+	/* Add Session-Timers related headers if the feature is active for this session.
+	   An exception to this behavior is the ACK request. Since Asterisk never requires 
+	   session-timers support from a remote end-point (UAS) in an INVITE, it must 
+	   not send 'Require: timer' header in the ACK request. Also, Require: header 
+	   is not applicable for CANCEL method. */
+	if (p->stimer && p->stimer->st_active == TRUE && p->stimer->st_active_peer_ua == TRUE 
+	    && sipmethod != SIP_ACK && sipmethod != SIP_CANCEL) {
 		char se_hdr[256];
 		snprintf(se_hdr, sizeof(se_hdr), "%d;refresher=%s", p->stimer->st_interval, 
 			strefresher2str(p->stimer->st_ref));
@@ -8767,6 +8772,7 @@ static int transmit_invite(struct sip_pvt *p, int sipmethod, int sdp, int init)
 		
 		snprintf(i2astr, sizeof(i2astr), "%d", p->stimer->st_interval);
 		add_header(&req, "Session-Expires", i2astr);
+		snprintf(i2astr, sizeof(i2astr), "%d", st_get_se(p, FALSE));
 		add_header(&req, "Min-SE", i2astr);
 	}