The following blog explains the difference between a LOCAL and REMOTE mode of jms integration with glassfish. If you configure your cluster with LOCAL (default) mode then one broker would be started for every instance in the cluster. If you change it to REMOTE you can achieve what you are asking for in (2).
http://weblogs.java.net/blog/rampsarathy/archive/2007/02/jms_service_ava.html
Also , note that if you want to create durable subscribers to the topic then the client id has to be unique, though your application is deployed homogeneously to all instances in the glassfish cluster, there would be 2 (number of instances) subscribers that are created for the topic. So if you have durable subscription then ensure that there is some uniqueness in the client id in your application.
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