boolean watchingRemoteStateChange;
public void onRemoteStateChange(final Callback<DeliveryState> cb) {
watchingRemoteStateChange = true;
final DeliveryState original = delivery.getRemoteState();
addWatch(new Watch() {
@Override
public boolean execute() {
if (original == null) {
if( delivery.getRemoteState()!=null ) {
cb.onSuccess(delivery.getRemoteState());