Put your EAR file anywhere, and when you want to deploy it call the deploy() operation of the jboss.system:service=MainDeployer MBean, passing in the full path (or URL) for the EAR file. You can do this programatically, via the JMC Console, or via twiddle.
Similarly, you can call undeploy to undeploy the application.
By the way, if you use this scheme, you will have to redeploy the application if you restart the app server.
thank you very much - I was under the impression that the ear file have to be located under the deploy directory of JBOSS