//Respond with a Data message that requires acknowledgement
dm = new DataMessage();
dm.setEof().setSessionID((byte)0x00).setPayload(
new byte[] {(byte)0x16,(byte)0x16}).setSize((short)2)
.setSessionID((byte) 0x00).setEof().setClose().setAckRequired();
dm.send(os);
//Verify that a properly formatted acknowledgement message is
//received
AcknowledgementMessage am = new AcknowledgementMessage();
try {
am.receive(is,getTimeout());