You also need to create a queue/topic depending upon what you need to do.
If you are trying Publish-subscribe go create a topic, otherwise create a queue in the weblogic console.
Then Use any of the IDEs and create a basic MDB. When you create a MDB tru
IDE( like JBuilder, Visual Cafe etc.,), All the details of descriptors will be taken care by the IDE. Take the EAR/JAR file to deploy.Make sure that your Topic/Queue is created before you attempt to deploy. Deploy it.
Then go to the weblogic help part (code section) and you will find a client to send a message to the Topic/Queue.
Modify the JNDI names in there and reusue them to send the message.
When a message hits the Topic/queue the onMessage() method gets run. Put in a System.out.println statement in there to print output.
It's easy.
GOOD LUCK!!