Index: channels/sig_pri.c
===================================================================
--- channels/sig_pri.c	(revision 355948)
+++ channels/sig_pri.c	(working copy)
@@ -5060,7 +5060,7 @@
 #endif	/* defined(HAVE_PRI_CALL_WAITING) */
 					{
 						/* We will not accept incoming call waiting calls. */
-						pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_INCOMPATIBLE_DESTINATION);
+						pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION);
 						break;
 					}
 #if defined(HAVE_PRI_CALL_WAITING)