From 647d2c800a105c09d42cb8da66e056cb7afa19ed Mon Sep 17 00:00:00 2001
From: Mark Michelson <mmichelson@digium.com>
Date: Tue, 1 Jul 2008 21:13:32 +0000
Subject: [PATCH] Merging Revision 127113 from trunk

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.0@127156 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---
 main/channel.c | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/main/channel.c b/main/channel.c
index f8406feb06..2c6dba1d0f 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -1679,15 +1679,31 @@ int __ast_answer(struct ast_channel *chan, unsigned int delay)
 	switch (chan->_state) {
 	case AST_STATE_RINGING:
 	case AST_STATE_RING:
-		if (chan->tech->answer)
-			res = chan->tech->answer(chan);
-		ast_setstate(chan, AST_STATE_UP);
-		ast_cdr_answer(chan->cdr);
-		ast_channel_unlock(chan);
-		if (delay)
+		if (delay) {
+			int needanswer = (chan->tech->answer != NULL);
+
+			ast_setstate(chan, AST_STATE_UP);
+			ast_cdr_answer(chan->cdr);
+			ast_channel_unlock(chan);
 			ast_safe_sleep(chan, delay);
+			/* don't tell the channel it has been answered until *after* the delay,
+			   so that the media path will be in place and usable when it wants to
+			   send media
+			*/
+			if (needanswer) {
+				ast_channel_lock(chan);
+				res = chan->tech->answer(chan);
+				ast_channel_unlock(chan);
+			}
+		} else {
+			if (chan->tech->answer) {
+				res = chan->tech->answer(chan);
+			}
+			ast_setstate(chan, AST_STATE_UP);
+			ast_cdr_answer(chan->cdr);
+			ast_channel_unlock(chan);
+		}
 		return res;
-		break;
 	case AST_STATE_UP:
 		ast_cdr_answer(chan->cdr);
 		break;