--- chan_zap.c.old	2007-10-10 13:39:53.000000000 -0700
+++ chan_zap.c	2007-10-12 09:21:08.000000000 -0700
@@ -8584,6 +8584,13 @@
 							if (option_verbose > 2)
 								ast_verbose(VERBOSE_PREFIX_3 "PROGRESS with cause code %d received\n", e->proceeding.cause);
 
+							if (e->proceeding.cause == 1 && option_verbose > 4) {
+								pri_hangup(pri->pri, pri->pvts[chanpos]->call, PRI_CAUSE_UNALLOCATED);
+								pri->pvts[chanpos]->owner->hangupcause == AST_CAUSE_UNALLOCATED;
+								pri->pvts[chanpos]->call = NULL;
+								pri->pvts[chanpos]->exten[0] = '\0';
+								f.subclass = AST_CONTROL_ANSWER;
+							}
 							/* Work around broken, out of spec USER_BUSY cause in a progress message */
 							if (e->proceeding.cause == AST_CAUSE_USER_BUSY) {
 								if (pri->pvts[chanpos]->owner) {