For a quick start, follow the steps below:
1. In <jboss-home>\server\default\deploy\directory... jbossmq-destinations-service.xml, jms-service.xml, jbossmq-service.xml are the three files that deal with jms stuff.
2. <jboss-home>\server\default\deploy\jbossmq-destinations-service.xml contains default destinations provided by JBoss. Say we choose the default topic "testTopic". When JBoss starts this is registered with the JNDI name of Topic/testTopic.
3. In the same file, u can also see the connectionfactory provided .. for eg java:/XAConnectionFactory.
4. So yr code cd be

//** code **//
Topic topic = (Topic)ctx.lookup("topic/testTopic");
TopicConnectionFactory tconFactory = (TopicConnectionFactory)ctx.lookup("java:/XAConnectionFactory");
TopicConnection tcon = tconFactory.createTopicConnection();
TopicSession tsession = tcon.createTopicSession(false, Session.AUTO_ACKNOWLEDGE);
TopicPublisher tpublisher = tsession.createPublisher(topic);
TextMessage msg = tsession.createTextMessage();
tcon.start();
msg.setText("Hello");
tpublisher.publish(msg);
tpublisher.close();
tsession.close();
tcon.close();

This shd help for a quick start. You can go thru the various messages posted in JBoss/JMS forum to understand, how's, what's, where's of JBOSS JMS. That's what i am trying to do. :-)

cheers...