A suite of Quick starts that have been written to demonstrate the use of Java EE 6 on JBoss AS7 have been written and are available here. As part of this suite we have written an example that uses JMS and MDB's to show how to deploy an MDB and post a message to it via a JMS client. The quick start itself can be found here and the Read me takes you through all the steps needed to do deploy and run the example.
The example also demonstrates how to deploy the example using Openshift. OpenShift is Red Hat's free, Cloud Application Platform as a Service offering which allows application developers and teams to build, test, deploy, and run their applications easily. Pete Muir has created a screencast which takes you step by step through how to do this.