Hmm...
It seems like you are trying to deploy a Topic called ianTest using the mbean solution. I'm not sure it you can do that in HornetQ (anyone else know this for sure?)
<mbean code="org.jboss.jms.server.destination.TopicService"
name="jboss.messaging.destination:service=Topic,name=ianTest"
xmbean-dd="xmdesc/Topic-xmbean.xml">
<depends optional-attribute-name="ServerPeer">jboss.messaging:service=ServerPeer</depends>
<depends>jboss.messaging:service=PostOffice</depends>
</mbean>
I believe (i'm far from sure as I haven't started using JBoss 6 yet) that you have to put the topic def. into "$JBOSS_HOME/server/XXX/deploy/hornetq/hornetq-jms.xml":
<topic name="ianTest">
<entry name="/topic/ianTest"/>
</topic>