I solved the problem by myself.
The ear deployer is missing what means that the EARDeployer MBean is not registered so you can deploy no ear archives.
There should be an ear-deployer.xml file in the deploy folder. Not sure if it is a bug or deliberate.
Thanks to the JBoss developer for the good architecture and the very good jmx management console.
How did you install JBoss? Did you use the installer or did you just unzip a distribution?
I used the nice installer!