I have a topic configured correctly like this, in jboss 5.1:
<mbean code="org.jboss.jms.server.destination.TopicService"
name="jboss.messaging.destination:service=Topic,name=GreetingsTopic"
xmbean-dd="xmdesc/Topic-xmbean.xml">
<depends optional-attribute-name="ServerPeer">jboss.messaging:service=ServerPeer
</depends>
<depends>jboss.messaging:service=PostOffice</depends>
</mbean>
I can see the topic being started ...