'Saving an old thread should not change its created date.'

def test_save_old_thread_created(self):

    t = ThreadFactory(created=YESTERDAY)
    t = Thread.objects.get(id=t.id)
    created = t.created
    t.title = 'new    title'
    t.save()
    t = Thread.objects.get(id=t.id)
    eq_(created, t.created)
