diff --git a/CHANGES.txt b/CHANGES.txt
index b64ca2f83d1..3ac2d995c89 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -337,6 +337,7 @@ Release 0.92.0 - Unreleased
    HBASE-4334  HRegion.get never validates row (Lars Hofhansl)
    HBASE-4494  AvroServer:: get fails with NPE on a non-existent row
                (Kay Kay)
+   HBASE-4481  TestMergeTool failed in 0.92 build 20
 
   TESTS
    HBASE-4450  test for number of blocks read: to serve as baseline for expected
diff --git a/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java b/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java
index cf83052f19d..d7a3c11a369 100644
--- a/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java
+++ b/src/test/java/org/apache/hadoop/hbase/util/TestMergeTool.java
@@ -60,6 +60,11 @@ public class TestMergeTool extends HBaseTestCase {
   public void setUp() throws Exception {
     // Set the timeout down else this test will take a while to complete.
     this.conf.setLong("hbase.zookeeper.recoverable.waittime", 1000);
+    // Make it so we try and connect to a zk that is not there (else we might
+    // find a zk ensemble put up by another concurrent test and this will
+    // mess up this test.  Choose unlikely port. Default test port is 21818.
+    // Default zk port is 2181.
+    this.conf.setInt("hbase.zookeeper.property.clientPort", 10001);
 
     this.conf.set("hbase.hstore.compactionThreshold", "2");