***************
*** 3345,3354 ****

  static void update_provisional_keepalive(struct sip_pvt *pvt, int with_sdp)
  {
-       AST_SCHED_DEL(sched, pvt->provisional_keepalive_sched_id);

        pvt->provisional_keepalive_sched_id = ast_sched_add(sched, PROVIS_KEEPALIVE_TIMEOUT,
                with_sdp ? send_provisional_keepalive_with_sdp : send_provisional_keepalive, pvt);
  }

  /*! \brief Transmit response on SIP request*/
--- 3345,3357 ----

  static void update_provisional_keepalive(struct sip_pvt *pvt, int with_sdp)
  {
+       AST_SCHED_DEL_UNREF(sched, pvt->provisional_keepalive_sched_id, dialog_unref(pvt));

        pvt->provisional_keepalive_sched_id = ast_sched_add(sched, PROVIS_KEEPALIVE_TIMEOUT,
                with_sdp ? send_provisional_keepalive_with_sdp : send_provisional_keepalive, pvt);
+       if (pvt->provisional_keepalive_sched_id > 0) {
+               dialog_ref(pvt);
+       }
  }

  /*! \brief Transmit response on SIP request*/
***************
*** 3374,3380 ****

        /* If we are sending a final response to an INVITE, stop retransmitting provisional responses */
        if (p->initreq.method == SIP_INVITE && reliable == XMIT_CRITICAL) {
-               AST_SCHED_DEL(sched, p->provisional_keepalive_sched_id);
        }

        res = (reliable) ?
--- 3377,3383 ----

        /* If we are sending a final response to an INVITE, stop retransmitting provisional responses */
        if (p->initreq.method == SIP_INVITE && reliable == XMIT_CRITICAL) {
+               AST_SCHED_DEL_UNREF(sched, p->provisional_keepalive_sched_id, dialog_unref(p));
        }

        res = (reliable) ?
***************
*** 4690,4696 ****
        AST_SCHED_DEL(sched, p->waitid);
        AST_SCHED_DEL(sched, p->autokillid);
        AST_SCHED_DEL(sched, p->request_queue_sched_id);
-       AST_SCHED_DEL(sched, p->provisional_keepalive_sched_id);
        AST_SCHED_DEL(sched, p->t38id);

        if (p->rtp) {
--- 4693,4699 ----
        AST_SCHED_DEL(sched, p->waitid);
        AST_SCHED_DEL(sched, p->autokillid);
        AST_SCHED_DEL(sched, p->request_queue_sched_id);
+       AST_SCHED_DEL_UNREF(sched, p->provisional_keepalive_sched_id, dialog_unref(p));
        AST_SCHED_DEL(sched, p->t38id);

        if (p->rtp) {