public MessageAck[] getAcks() {
   MessageAck rc[] = new MessageAck[acks.size()];
   int count = 0;
   for (Iterator<RemoveMessageCommand> iter = acks.iterator(); iter.hasNext(); ) {
     RemoveMessageCommand cmd = iter.next();
     rc[count++] = cmd.getMessageAck();
   }
   return rc;
 }