static void on_tp_state_callback(pjsip_transport *tp,
				 pjsip_transport_state state,
				 const pjsip_transport_state_info *info)
{
    if (pjsua_var.ua_cfg.cb.on_transport_state) {
	(*pjsua_var.ua_cfg.cb.on_transport_state)(tp, state, info);
    }
    if (pjsua_var.old_tp_cb) {
	(*pjsua_var.old_tp_cb)(tp, state, info);
    }
    pjsua_acc_on_tp_state_changed(tp, state, info);
}
static void on_tp_state_callback(pjsip_transport *tp,
				 pjsip_transport_state state,
				 const pjsip_transport_state_info *info)
{
    if (pjsua_var.ua_cfg.cb.on_transport_state) {
	(*pjsua_var.ua_cfg.cb.on_transport_state)(tp, state, info);
    }
    if (pjsua_var.old_tp_cb) {
	(*pjsua_var.old_tp_cb)(tp, state, info);
    }
    pjsua_acc_on_tp_state_changed(tp, state, info);
}