JMS messaging question

    I'm having some trouble with JMS messages. I have the following method
to put a message to a SonicMQ queue via JMS and I want to read the response
message that comes back. I am putting the message successfully, but the
code times out every time when trying to get the response. If anyone can see
something I have wrong in the code, please let me know. I'm new to JMS so I
assume that I'm missing something very basic. The getCorrelationId method
just creates a correlation id based on some literals and a timestamp.

 public String sendXml(String pXML) throws ConnectionException {
      if (pXML == null)
           throw new ConnectionException("No XML data was entered.");

      String correlationId = null;

      try {
           QueueSession queueSession =
mQueueConnection.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
           QueueSender queueSender = queueSession.createSender(mQueue);

           TextMessage message = queueSession.createTextMessage();
           message.setJMSReplyTo((Queue)mJndiContext.lookup(mResponseQueue));
           message.setJMSExpiration(mTimeout);
           correlationId = getCorrelationId(1);
           message.setJMSCorrelationID(correlationId);
           message.setText(pXML);

           queueSender.send(message, DeliveryMode.PERSISTENT,
Message.DEFAULT_PRIORITY, mTimeout);
           String JMSCorrelationId = message.getJMSMessageID();
      } catch (JMSException e) {
           throw new ConnectionException("Got JMS exception trying to
connect to the queue " + mQueue + ".");
      } catch (NamingException ne) {
           throw new ConnectionException("Got naming exception trying to
lookup queue " + mQueue + ".");
      }

      try {
           QueueSession queueSession =
mQueueConnection.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
           Queue receiveQueue = (Queue)mJndiContext.lookup(mResponseQueue);
           QueueReceiver queueReceiver =
queueSession.createReceiver(receiveQueue, correlationId);
           Message msg = queueReceiver.receive(mTimeout);

          if (msg != null) {
                String textMsg = null;
                if (msg instanceof TextMessage) {
                     return ((TextMessage) msg).getText().toString();
                } else if (msg instanceof BytesMessage) {
                     ByteArrayOutputStream bytes = new
ByteArrayOutputStream();
                     byte[] byteBuffer = new byte[1024];
                     int read = 0;
                     while ((read = ((BytesMessage)
msg).readBytes(byteBuffer)) != -1) {
                          bytes.write(byteBuffer, 0, read);
                     }
                     return new String(bytes.toByteArray());
                } else {
                     throw new ConnectionException("Did not receive a
readable message.");
               }
          } else {
                throw new ConnectionException("Did not receive a response in
the time allotted.");
          }
      } catch (JMSException e) {
           throw new ConnectionException("Got JMS exception trying to
connect to the queue " + mResponseQueue + ".");
      } catch (NamingException ne) {
           throw new ConnectionException("Got naming exception trying to
lookup queue " + mResponseQueue + ".");
      }

 }