Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 47221)
+++ channels/chan_sip.c	(working copy)
@@ -10748,6 +10748,7 @@
 {
 	struct ast_channel *c=NULL;
 	int res;
+	int attempttransferres = 0;
 	struct ast_channel *transfer_to;
 	char *transfercontext = NULL;
 
@@ -10767,12 +10768,14 @@
 		if (!ignore) {
 			if (p->refer_call) {
 				ast_log(LOG_DEBUG,"202 Accepted (supervised)\n");
-				attempt_transfer(p, p->refer_call);
-				if (p->refer_call->owner)
-					ast_mutex_unlock(&p->refer_call->owner->lock);
-				ast_mutex_unlock(&p->refer_call->lock);
-				p->refer_call = NULL;
-				ast_set_flag(p, SIP_GOTREFER);	
+				attempttransferres = attempt_transfer(p, p->refer_call);
+				if (attempttransferres == 0) {
+					if (p->refer_call->owner)
+						ast_mutex_unlock(&p->refer_call->owner->lock);
+					ast_mutex_unlock(&p->refer_call->lock);
+					p->refer_call = NULL;
+					ast_set_flag(p, SIP_GOTREFER);	
+				}
 			} else {
 				ast_log(LOG_DEBUG,"202 Accepted (blind)\n");
 				c = p->owner;
@@ -10802,12 +10805,16 @@
 				}
 				ast_set_flag(p, SIP_GOTREFER);	
 			}
-			transmit_response(p, "202 Accepted", req);
-			transmit_notify_with_sipfrag(p, seqno);
-			/* Always increment on a BYE */
-			if (!nobye) {
-				transmit_request_with_auth(p, SIP_BYE, 0, 1, 1);
-				ast_set_flag(p, SIP_ALREADYGONE);	
+			if (attempttransferres == 0) {
+				transmit_response(p, "202 Accepted", req);
+				transmit_notify_with_sipfrag(p, seqno);
+				/* Always increment on a BYE */
+				if (!nobye) {
+					transmit_request_with_auth(p, SIP_BYE, 0, 1, 1);
+					ast_set_flag(p, SIP_ALREADYGONE);	
+				}
+			} else {
+				transmit_response(p, "603 Declined", req);
 			}
 		}
 	}