hbase is not deleting the cell when a Put with a KeyValue, KeyValue.Type.Delete is submitted

    @Test
    public void testHbasePutDeleteCell() throws Exception {
        TableName tableName = TableName.valueOf("my_test");
        Configuration configuration = HBaseConfiguration.create();
        HTableInterface table = new HTable(configuration, tableName);
        final String rowKey = "12345";
        final byte[] familly = Bytes.toBytes("default");
        // put one row
        Put put = new Put(Bytes.toBytes(rowKey));
        put.add(familly, Bytes.toBytes("A"), Bytes.toBytes("a"));
        put.add(familly, Bytes.toBytes("B"), Bytes.toBytes("b"));
        put.add(familly, Bytes.toBytes("C"), Bytes.toBytes("c"));
        table.put(put);
        // get row back and assert the values
        Get get = new Get(Bytes.toBytes(rowKey));
        Result result = table.get(get);
        Assert.isTrue(Bytes.toString(result.getValue(familly, Bytes.toBytes("A"))).equals("a"), "Column A value should be a");
        Assert.isTrue(Bytes.toString(result.getValue(familly, Bytes.toBytes("B"))).equals("b"), "Column B value should be b");
        Assert.isTrue(Bytes.toString(result.getValue(familly, Bytes.toBytes("C"))).equals("c"), "Column C value should be c");
        // put the same row again with C column deleted
        put = new Put(Bytes.toBytes(rowKey));
        put.add(familly, Bytes.toBytes("A"), Bytes.toBytes("a"));
        put.add(familly, Bytes.toBytes("B"), Bytes.toBytes("b"));
        put.add(new KeyValue(Bytes.toBytes(rowKey), familly, Bytes.toBytes("C"), HConstants.LATEST_TIMESTAMP, KeyValue.Type.DeleteColumn));
        table.put(put);
        // get row back and assert the values
        get = new Get(Bytes.toBytes(rowKey));
        result = table.get(get);
        Assert.isTrue(Bytes.toString(result.getValue(familly, Bytes.toBytes("A"))).equals("a"), "Column A value should be a");
        Assert.isTrue(Bytes.toString(result.getValue(familly, Bytes.toBytes("B"))).equals("b"), "Column A value should be b");
        Assert.isTrue(result.getValue(familly, Bytes.toBytes("C")) == null, "Column C should not exists");
    }

hbase(main):029:0> scan 'my_test'
ROW                                                   COLUMN+CELL                                                                                                                                                 
 12345                                                column=default:A, timestamp=1408473082290, value=a                                                                                                          
 12345                                                column=default:B, timestamp=1408473082290, value=b                                                                                                          
 12345                                                column=default:C, timestamp=1408473082290, value=