diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 7edc98da351..b363e8027ff 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -276,6 +276,9 @@ Release 0.23.1 - Unreleased
     MAPREDUCE-3537. Fix race condition in DefaultContainerExecutor which led
     to container localization occuring in wrong directories. (acmurthy) 
 
+    MAPREDUCE-3542. Support "FileSystemCounter" legacy counter group name for
+    compatibility. (tomwhite)
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/counters/AbstractCounters.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/counters/AbstractCounters.java
index d7c12375b1c..b09aaef7934 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/counters/AbstractCounters.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/counters/AbstractCounters.java
@@ -76,6 +76,7 @@ public abstract class AbstractCounters<C extends Counter,
                   TaskCounter.class.getName());
     legacyMap.put("org.apache.hadoop.mapred.JobInProgress$Counter",
                   JobCounter.class.getName());
+    legacyMap.put("FileSystemCounter", FileSystemCounter.class.getName());
   }
 
   private final Limits limits = new Limits();
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapred/TestCounters.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapred/TestCounters.java
index 4ce1c8159d2..bdd5bed4f3a 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapred/TestCounters.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapred/TestCounters.java
@@ -22,6 +22,8 @@ import static org.junit.Assert.assertEquals;
 import java.io.IOException;
 import java.text.ParseException;
 
+import org.apache.hadoop.mapred.Counters.Counter;
+import org.apache.hadoop.mapreduce.FileSystemCounter;
 import org.apache.hadoop.mapreduce.JobCounter;
 import org.apache.hadoop.mapreduce.TaskCounter;
 import org.junit.Test;
@@ -102,6 +104,7 @@ public class TestCounters {
     Counters counters = new Counters();
     counters.incrCounter(TaskCounter.MAP_INPUT_RECORDS, 1);
     counters.incrCounter(JobCounter.DATA_LOCAL_MAPS, 1);
+    counters.findCounter("file", FileSystemCounter.BYTES_READ).increment(1);
     
     assertEquals("New name", 1, counters.findCounter(
         TaskCounter.class.getName(), "MAP_INPUT_RECORDS").getValue());
@@ -114,6 +117,14 @@ public class TestCounters {
     assertEquals("Legacy name", 1, counters.findCounter(
         "org.apache.hadoop.mapred.JobInProgress$Counter",
         "DATA_LOCAL_MAPS").getValue());
+
+    assertEquals("New name", 1, counters.findCounter(
+        FileSystemCounter.class.getName(), "FILE_BYTES_READ").getValue());
+    assertEquals("New name and method", 1, counters.findCounter("file",
+        FileSystemCounter.BYTES_READ).getValue());
+    assertEquals("Legacy name", 1, counters.findCounter(
+        "FileSystemCounter",
+        "FILE_BYTES_READ").getValue());
   }
   
   public static void main(String[] args) throws IOException {