* @return The message that came in reply to the original send.
* @throws InterruptedException if interrupted while waiting
*/
public final <T> Object sendAndWait(final T message, final long timeout, final TimeUnit units) throws InterruptedException {
final ResultWaiter<Object> to = new ResultWaiter<Object>();
send(new ActorMessage(message, to));
return to.getResult(timeout, units);
}