I am not sure what the official take on this issue is at the moment. I remember Scott telling me that we will need to add explicit dependencies (or such) to make the russian doll ordering to work.
For example, I have a situation in the test suite as follows:
org.jboss.test.security.test.DeepCopySubjectUnitTestCase
Caused by: java.lang.IllegalStateException: jboss.security.tests:service=DynamicLoginConfigDeepCopyTest is already installed. at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:525) at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:398) at org.jboss.system.ServiceController.doInstall(ServiceController.java:641)