diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index d355bf4f80..7d5ea8cd22 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -361,6 +361,8 @@ Release 0.23.1 - UNRELEASED
     HDFS-2822. processMisReplicatedBlock incorrectly identifies
     under-construction blocks as under-replicated. (todd)
 
+    HDFS-442. dfsthroughput in test jar throws NPE (harsh)
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BenchmarkThroughput.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BenchmarkThroughput.java
index 77ac2652fd..db06c0d2ee 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BenchmarkThroughput.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BenchmarkThroughput.java
@@ -193,6 +193,10 @@ public int run(String[] args) throws IOException {
     BUFFER_SIZE = conf.getInt("dfsthroughput.buffer.size", 4 * 1024);
 
     String localDir = conf.get("mapred.temp.dir");
+    if (localDir == null) {
+      localDir = conf.get("hadoop.tmp.dir");
+      conf.set("mapred.temp.dir", localDir);
+    }
     dir = new LocalDirAllocator("mapred.temp.dir");
 
     System.setProperty("test.build.data", localDir);