Send a 100 Trying response when we detect a spiral.

This was problematic during spiral tests at SIPit...
along with some other things as well.



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@219320 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -14659,6 +14659,7 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 			if (option_debug > 2) {
 				ast_log(LOG_DEBUG, "Potential spiral detected. Original RURI was %s, new RURI is %s\n", p->initreq.rlPart2, req->rlPart2);
 			}
+			transmit_response(p, "100 Trying", req);
 			if (at) {
 				*at = '\0';
 			}