Since I could not find a simple example demonstrating Seam-MDB (Mesage Driven Bean) usage, I am posting one for the benefit of others. We will create a simple EJB3 MDB called "Phone" and send a message to it from a EJB3 stateless bean (I assume you know how to create and use stateless beans).

In 3 steps:

Step 1: Here is the code for the MDP (Phone.java):
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package com.mkl.message;

import javax.jms.*;
import javax.ejb.MessageDriven;
import javax.ejb.ActivationConfigProperty;

@MessageDriven(name="PhoneMessageBean", activationConfig = {
     @ActivationConfigProperty(propertyName="destinationType", propertyValue="javax.jms.Queue"),
     @ActivationConfigProperty(propertyName="destination", propertyValue="queue/phoneQueue")
 })
public class Phone implements MessageListener {

 @Override
 public void onMessage(Message msg) {
  // TODO Auto-generated method stub
  TextMessage textMsg = (TextMessage) msg;
  try {
   System.out.println("Received Phone Call:" + textMsg.getText());
  } catch (JMSException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }
}
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Step 2: Here is the component addition to components.xml

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<component name="phoneQueueSender"
          class="org.jboss.seam.jms.ManagedQueueSender">
    <property name="queueJndiName">queue/phoneQueue</property>
</component>

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Step 3: Here is the stateless bean function which sends a message
(YOU NEED TO IMPORT javax.jms.*)
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 @In(create=true)
 private transient QueueSender phoneQueueSender;
 @In(create=true)
 private transient QueueSession queueSession;

 public void make_a_call (){
       try
       {
          phoneQueueSender.send( queueSession.createTextMessage("You are in trouble"));
       }
       catch (Exception ex)
       {
       ex.printStackTrace();
          throw new RuntimeException(ex);
       }
    }

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