public void testSubjectFollowsSpawnedThreads()
    {
        // Never allow access to teacher
        rp.addRules(Teacher.class, new Rules()
        {
            public boolean allow(Object subject, Object object)
            {
                return false;
            }
        });
        Teacher teacher = new Teacher("Mr. Brown");
        final ClassRoom english = new ClassRoom(teacher);

        filter.setSubject(new Object());
        // Verify subject set on current thread
        assertNull(english.getTeacher());

        final boolean [] blocked = {false};
        final boolean [] finished = {false};
        Thread thread = new Thread(new Runnable()
        {
            public void run()
            {
                blocked[0] = (english.getTeacher() == null);
                finished[0] = true;
            }
        });
        thread.start();
        while (!finished[0])
        {
            Thread.yield();
        }
        assertTrue(blocked[0]);
    }