diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 3e5899f92b3..9ae1dfb612b 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -224,6 +224,9 @@ Release 0.23.1 - Unreleased
     MAPREDUCE-3510. Capacity Scheduler inherited ACLs not displayed by mapred queue 
     -showacls (Jonathan Eagles via mahadev)
 
+    MAPREDUCE-3537. Fix race condition in DefaultContainerExecutor which led
+    to container localization occuring in wrong directories. (acmurthy) 
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/DefaultContainerExecutor.java b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/DefaultContainerExecutor.java
index bd953174aa0..3d460531154 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/DefaultContainerExecutor.java
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/DefaultContainerExecutor.java
@@ -75,7 +75,7 @@ public class DefaultContainerExecutor extends ContainerExecutor {
   }
   
   @Override
-  public void startLocalizer(Path nmPrivateContainerTokensPath,
+  public synchronized void startLocalizer(Path nmPrivateContainerTokensPath,
       InetSocketAddress nmAddr, String user, String appId, String locId,
       List<String> localDirs, List<String> logDirs)
       throws IOException, InterruptedException {