diff --git a/src/java/org/apache/poi/poifs/storage/DocumentBlock.java b/src/java/org/apache/poi/poifs/storage/DocumentBlock.java
index f6d0d92b4..7af3487fa 100644
--- a/src/java/org/apache/poi/poifs/storage/DocumentBlock.java
+++ b/src/java/org/apache/poi/poifs/storage/DocumentBlock.java
@@ -62,6 +62,7 @@ import java.io.OutputStream;
 import java.util.Arrays;
 
 import org.apache.poi.poifs.common.POIFSConstants;
+import org.apache.poi.util.IOUtils;
 import org.apache.poi.util.IntegerField;
 import org.apache.poi.util.LittleEndian;
 import org.apache.poi.util.LittleEndianConsts;
@@ -106,7 +107,7 @@ public class DocumentBlock
         throws IOException
     {
         this();
-        int count = stream.read(_data);
+        int count = IOUtils.readFully(stream, _data);
 
         _bytes_read = (count == -1) ? 0
                                     : count;
diff --git a/src/java/org/apache/poi/poifs/storage/HeaderBlockReader.java b/src/java/org/apache/poi/poifs/storage/HeaderBlockReader.java
index 015d455d2..ad7736851 100644
--- a/src/java/org/apache/poi/poifs/storage/HeaderBlockReader.java
+++ b/src/java/org/apache/poi/poifs/storage/HeaderBlockReader.java
@@ -60,6 +60,7 @@ import java.io.*;
 import java.util.*;
 
 import org.apache.poi.poifs.common.POIFSConstants;
+import org.apache.poi.util.IOUtils;
 import org.apache.poi.util.IntegerField;
 import org.apache.poi.util.LittleEndian;
 import org.apache.poi.util.LittleEndianConsts;
@@ -104,7 +105,7 @@ public class HeaderBlockReader
         throws IOException
     {
         _data = new byte[ POIFSConstants.BIG_BLOCK_SIZE ];
-        int byte_count = stream.read(_data);
+        int byte_count = IOUtils.readFully(stream, _data);
 
         if (byte_count != POIFSConstants.BIG_BLOCK_SIZE)
         {
diff --git a/src/java/org/apache/poi/poifs/storage/RawDataBlock.java b/src/java/org/apache/poi/poifs/storage/RawDataBlock.java
index 862fd8ca2..863b6108e 100644
--- a/src/java/org/apache/poi/poifs/storage/RawDataBlock.java
+++ b/src/java/org/apache/poi/poifs/storage/RawDataBlock.java
@@ -56,6 +56,7 @@
 package org.apache.poi.poifs.storage;
 
 import org.apache.poi.poifs.common.POIFSConstants;
+import org.apache.poi.util.IOUtils;
 
 import java.io.*;
 
@@ -84,7 +85,7 @@ public class RawDataBlock
         throws IOException
     {
         _data = new byte[ POIFSConstants.BIG_BLOCK_SIZE ];
-        int count = stream.read(_data);
+        int count = IOUtils.readFully(stream, _data);
 
         if (count == -1)
         {
diff --git a/src/testcases/org/apache/poi/poifs/filesystem/TestDocument.java b/src/testcases/org/apache/poi/poifs/filesystem/TestDocument.java
index af417fad1..2e9fd0282 100644
--- a/src/testcases/org/apache/poi/poifs/filesystem/TestDocument.java
+++ b/src/testcases/org/apache/poi/poifs/filesystem/TestDocument.java
@@ -107,7 +107,7 @@ public class TestDocument
         {
             array[ j ] = ( byte ) j;
         }
-        document = new POIFSDocument("foo", new ByteArrayInputStream(array));
+        document = new POIFSDocument("foo", new SlowInputStream(new ByteArrayInputStream(array)));
         checkDocument(document, array);
 
         // verify correct number of blocks get created for document