MessageReference ref = consumer.waitForNextReference(QueueImplTest.TIMEOUT);
Assert.assertEquals(ref7, ref);
long now2 = System.currentTimeMillis();
Assert.assertTrue(now2 - now >= 3000);
ref = consumer.waitForNextReference(QueueImplTest.TIMEOUT);
Assert.assertEquals(ref6, ref);
now2 = System.currentTimeMillis();
Assert.assertTrue(now2 - now >= 4000);
ref = consumer.waitForNextReference(QueueImplTest.TIMEOUT);