Duplicate undeployment of unpacked nested modules on jboss shutdown

When jboss shutdowns the MainDeployer goes through the list of deployment in reverse order and undeploys them. The problem is that unpacked nested deployments, e.g.:

./deploy/jbossws14.sar/jbossws.beans

are undeployed as part of the undeployment of the enclosing unit (i.e. jbossws14.sar).

After that an attempt is made to be undeployed again and spurious warnings maybe produced, like in JBAS-3471.