diff --git a/src/test/java/net/openhft/chronicle/map/DemoChronicleMapTest.java b/src/test/java/net/openhft/chronicle/map/DemoChronicleMapTest.java
index 3a7db30f9..79d73449f 100755
--- a/src/test/java/net/openhft/chronicle/map/DemoChronicleMapTest.java
+++ b/src/test/java/net/openhft/chronicle/map/DemoChronicleMapTest.java
@@ -9,8 +9,7 @@ import org.junit.Test;
 import java.io.File;
 import java.util.Map;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.*;
 
 public class DemoChronicleMapTest {
 
@@ -57,6 +56,52 @@ public class DemoChronicleMapTest {
             assertNotNull(v);
         }
     }
+
+    @Test
+    @Ignore
+    public void testMapLocked() throws Exception {
+        File file = File.createTempFile("DummyOrders", ".test");
+        file.deleteOnExit();
+        int maxEntries = 1000;
+        ChronicleMap<IntValue, DemoOrderVOInterface> map = ChronicleMapBuilder
+                .of(IntValue.class, DemoOrderVOInterface.class)
+                .putReturnsNull(true)
+                .removeReturnsNull(true)
+                .entries(maxEntries)
+                .createPersistedTo(file);
+
+
+        IntValue key = DataValueClasses.newInstance(IntValue.class);
+
+        DemoOrderVOInterface value = DataValueClasses.newDirectReference(DemoOrderVOInterface.class);
+        DemoOrderVOInterface value2 = DataValueClasses.newDirectReference(DemoOrderVOInterface.class);
+
+        // Initially populate the map
+        for (int i = 0; i < maxEntries; i++) {
+            key.setValue(i);
+
+            try (WriteContext wc = map.acquireUsingLocked(key, value)) {
+                // TODO Shouldn't throw an NPE, because acquire should set the value.
+                value.setSymbol("IBM-" + i);
+                value.addAtomicOrderQty(1000);
+            }
+
+            try (ReadContext rc = map.getUsingLocked(key, value2)) {
+                assertTrue(rc.present());
+                assertEquals("IBM-" + i, value.getSymbol());
+                assertEquals(1000, value.getOrderQty(), 0.0);
+            }
+        }
+
+        for (Map.Entry<IntValue, DemoOrderVOInterface> entry : map.entrySet()) {
+
+            IntValue k = entry.getKey();
+            DemoOrderVOInterface v = entry.getValue();
+
+            System.out.println(String.format("Key %d %s", k.getValue(), v == null ? "<null>" : v.getSymbol()));
+            assertNotNull(v);
+        }
+    }
 }
 
 interface DemoOrderVOInterface {