The org.jboss.security.SecurityAssociation.ThreadLocal system property which controls whether the SecurityAssociation thread locals are java.lang.ThreadLocal or InheritableThreadLocal is not being used for the newer thread local stacks such as RunAsThreadLocalStack and SubjectThreadLocalStack. The behavior of passing the thread local data to child threads should be controlled consistently by the org.jboss.security.SecurityAssociation.ThreadLocal system property.