JMS physical destination objects are maintained by Sun Java System Message Queue brokers. The queue named mq.sys.dmq is the system destination, to which expired and undeliverable messages are redirected.
Note - If you are trying to view the JMS Physical Destinations using the default-config, you will see an error message. In Application Server 9.1, default-config is a template of configuration information and hence JMS operations (such as list and create) cannot be executed for the default-config. These JMS operations can, however, be executed for the configurations of your cluster or stand-alone instances.