Index: channels/chan_mgcp.c
===================================================================
--- channels/chan_mgcp.c	(revision 89965)
+++ channels/chan_mgcp.c	(working copy)
@@ -2694,6 +2694,7 @@
 			transmit_notify_request(sub, "G/cg");
 			/*zt_wait_event(p->subs[index].zfd);*/
 			ast_hangup(chan);
+			memset(p->dtmf_buf, 0, sizeof(p->dtmf_buf));
 			return NULL;
 		} else if (p->hascallwaiting && p->callwaiting && !strcmp(p->dtmf_buf, "*70")) {
 			if (option_verbose > 2) {