--- channels/chan_zap.c.orig	2004-03-03 17:42:33.000000000 -0800
+++ channels/chan_zap.c	2004-03-03 18:19:15.000000000 -0800
@@ -6497,9 +6497,9 @@
 						if (!pri->pvt[chan]->alreadyhungup) {
 							/* we're calling here zt_hangup so once we get there we need to clear p->call after calling pri_hangup */
 							pri->pvt[chan]->alreadyhungup = 1;
-							pri->pvt[chan]->owner->hangupcause = hangup_pri2cause(e->hangup.cause);
 							/* Queue a BUSY instead of a hangup if our cause is appropriate */
 							if (pri->pvt[chan]->owner) {
+								pri->pvt[chan]->owner->hangupcause = hangup_pri2cause(e->hangup.cause);
 								switch(e->hangup.cause) {
 								case PRI_CAUSE_USER_BUSY:
 									pri->pvt[chan]->subs[SUB_REAL].needbusy =1;