I have trouble coming up with a failing test for this. This is what I tried (and it passed):

 public void testDurableSubscriptionWithPeriodsInName() throws Exception
 {
 ConnectionFactory cf = (ConnectionFactory)ic.lookup("ConnectionFactory");
 Topic topic = (Topic)ic.lookup("/topic/Topic");

 Connection conn = cf.createConnection();
 conn.setClientID(".client.id.with.periods.");

 Session s = conn.createSession(false, Session.AUTO_ACKNOWLEDGE);

 TopicSubscriber subscriber = s.createDurableSubscriber(topic, ".subscription.name.with.periods.");

 s.createProducer(topic).send(s.createTextMessage("Subscription test"));

 conn.start();

 Message m = subscriber.receive(1000L);

 assertNotNull(m);
 assertTrue(m instanceof TextMessage);

 subscriber.close();

 s.unsubscribe(".subscription.name.with.periods.");

 conn.close();
 }

Madhu- please post your full stack trace - just the error message doesn't give us much to go on.

I got it - have to undeploy/redeploy the topic to get the error.

Fixed. http://jira.jboss.com/jira/browse/JBMESSAGING-1008 is the issue, for future reference.