public virtual void TestLock()
        {
            mm.Lock("key1");

            var latch = new CountdownEvent(1);
            var t     = new Thread(delegate(object o)
            {
                if (!mm.TryLock("key1"))
                {
                    latch.Signal();
                }
            });

            t.Start();

            Assert.IsTrue(latch.Wait(TimeSpan.FromSeconds(5)));
            mm.ForceUnlock("key1");
        }