diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 364aa720b43..d077798da94 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -196,6 +196,9 @@ Branch-2 ( Unreleased changes )
 
     MAPREDUCE-4376. TestClusterMRNotification times out (Kihwal Lee via bobby)
 
+    MAPREDUCE-4383. HadoopPipes.cc needs to include unistd.h.
+    (Andy Isaacson via eli)
+
 Release 2.0.0-alpha - 05-23-2012
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-tools/hadoop-pipes/src/main/native/pipes/impl/HadoopPipes.cc b/hadoop-tools/hadoop-pipes/src/main/native/pipes/impl/HadoopPipes.cc
index 0e264255487..1d2fc953a46 100644
--- a/hadoop-tools/hadoop-pipes/src/main/native/pipes/impl/HadoopPipes.cc
+++ b/hadoop-tools/hadoop-pipes/src/main/native/pipes/impl/HadoopPipes.cc
@@ -30,6 +30,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <strings.h>
+#include <unistd.h>
 #include <sys/socket.h>
 #include <pthread.h>
 #include <iostream>