Index: channels/sig_pri.c
===================================================================
--- channels/sig_pri.c	(revision 299572)
+++ channels/sig_pri.c	(working copy)
@@ -6446,10 +6446,11 @@
 			chan->_softhangup |= AST_SOFTHANGUP_DEV;
 			res = 0;
 		} else if (!p->progress && p->pri && !p->outgoing) {
+			chan->hangupcause = AST_CAUSE_USER_BUSY;
 			if (p->pri->pri) {
 				if (!pri_grab(p, p->pri)) {
 #ifdef HAVE_PRI_PROG_W_CAUSE
-					pri_progress_with_cause(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1, PRI_CAUSE_USER_BUSY); /* cause = 17 */
+					pri_progress_with_cause(p->pri->pri, p->call, PVT_TO_CHANNEL(p), 1, chan->hangupcause);
 #else
 					pri_progress(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1);
 #endif
@@ -6523,16 +6524,36 @@
 		res = 0;
 		break;
 	case AST_CONTROL_CONGESTION:
-		chan->hangupcause = AST_CAUSE_CONGESTION;
 		if (p->priindication_oob || p->no_b_channel) {
-			chan->hangupcause = AST_CAUSE_SWITCH_CONGESTION;
+			/* There are many cause codes that generate an AST_CONTROL_CONGESTION. */
+			switch (chan->hangupcause) {
+			case AST_CAUSE_USER_BUSY:
+			case AST_CAUSE_NORMAL_CLEARING:
+			case 0:/* Cause has not been set. */
+				/* Supply a more appropriate cause. */
+				chan->hangupcause = AST_CAUSE_SWITCH_CONGESTION;
+				break;
+			default:
+				break;
+			}
 			chan->_softhangup |= AST_SOFTHANGUP_DEV;
 			res = 0;
 		} else if (!p->progress && p->pri && !p->outgoing) {
+			/* There are many cause codes that generate an AST_CONTROL_CONGESTION. */
+			switch (chan->hangupcause) {
+			case AST_CAUSE_USER_BUSY:
+			case AST_CAUSE_NORMAL_CLEARING:
+			case 0:/* Cause has not been set. */
+				/* Supply a more appropriate cause. */
+				chan->hangupcause = AST_CAUSE_SWITCH_CONGESTION;
+				break;
+			default:
+				break;
+			}
 			if (p->pri->pri) {
 				if (!pri_grab(p, p->pri)) {
 #ifdef HAVE_PRI_PROG_W_CAUSE
-					pri_progress_with_cause(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1, PRI_CAUSE_SWITCH_CONGESTION); /* cause = 42 */
+					pri_progress_with_cause(p->pri->pri, p->call, PVT_TO_CHANNEL(p), 1, chan->hangupcause);
 #else
 					pri_progress(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1);
 #endif