diff --git a/ChangeLog b/ChangeLog
index 3d80a3da..c3de9f7f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2010-06-12  Tatsuhiro Tsujikawa  <t-tujikawa@users.sourceforge.net>
+
+	Made protected member variable private.
+	* src/UTMetadataDataExtensionMessage.cc
+	* src/UTMetadataExtensionMessage.h
+	* src/UTMetadataRejectExtensionMessage.cc
+	* src/UTMetadataRequestExtensionMessage.cc
+
 2010-06-12  Tatsuhiro Tsujikawa  <t-tujikawa@users.sourceforge.net>
 
 	Renamed member variables
diff --git a/src/UTMetadataDataExtensionMessage.cc b/src/UTMetadataDataExtensionMessage.cc
index d32b23c1..85b0efe0 100644
--- a/src/UTMetadataDataExtensionMessage.cc
+++ b/src/UTMetadataDataExtensionMessage.cc
@@ -57,28 +57,28 @@ std::string UTMetadataDataExtensionMessage::getPayload()
 {
   BDE dict = BDE::dict();
   dict["msg_type"] = 1;
-  dict["piece"] = _index;
+  dict["piece"] = getIndex();
   dict["total_size"] = _totalSize;
   return bencode::encode(dict)+_data;
 }
 
 std::string UTMetadataDataExtensionMessage::toString() const
 {
-  return strconcat("ut_metadata data piece=", util::uitos(_index));
+  return strconcat("ut_metadata data piece=", util::uitos(getIndex()));
 }
 
 void UTMetadataDataExtensionMessage::doReceivedAction()
 {
-  if(_tracker->tracks(_index)) {
+  if(_tracker->tracks(getIndex())) {
     if(_logger->debug()) {
       _logger->debug("ut_metadata index=%lu found in tracking list",
-                     static_cast<unsigned long>(_index));
+                     static_cast<unsigned long>(getIndex()));
     }
-    _tracker->remove(_index);
+    _tracker->remove(getIndex());
     _pieceStorage->getDiskAdaptor()->writeData
       (reinterpret_cast<const unsigned char*>(_data.c_str()), _data.size(),
-       _index*METADATA_PIECE_SIZE);
-    _pieceStorage->completePiece(_pieceStorage->getPiece(_index));
+       getIndex()*METADATA_PIECE_SIZE);
+    _pieceStorage->completePiece(_pieceStorage->getPiece(getIndex()));
     if(_pieceStorage->downloadFinished()) {
       std::string metadata = util::toString(_pieceStorage->getDiskAdaptor());
       unsigned char infoHash[INFO_HASH_LENGTH];
@@ -99,7 +99,7 @@ void UTMetadataDataExtensionMessage::doReceivedAction()
   } else {
     if(_logger->debug()) {
       _logger->debug("ut_metadata index=%lu is not tracked",
-                     static_cast<unsigned long>(_index));
+                     static_cast<unsigned long>(getIndex()));
     }
   }
 }
diff --git a/src/UTMetadataExtensionMessage.h b/src/UTMetadataExtensionMessage.h
index 1053ecc4..d758a0a2 100644
--- a/src/UTMetadataExtensionMessage.h
+++ b/src/UTMetadataExtensionMessage.h
@@ -40,7 +40,7 @@
 namespace aria2 {
 
 class UTMetadataExtensionMessage:public ExtensionMessage {
-protected:
+private:
   uint8_t _extensionMessageID;
 
   size_t _index;
@@ -64,7 +64,7 @@ public:
     _index = index;
   }
 
-  size_t getIndex()
+  size_t getIndex() const
   {
     return _index;
   }
diff --git a/src/UTMetadataRejectExtensionMessage.cc b/src/UTMetadataRejectExtensionMessage.cc
index e6855c10..53cadb9b 100644
--- a/src/UTMetadataRejectExtensionMessage.cc
+++ b/src/UTMetadataRejectExtensionMessage.cc
@@ -49,13 +49,13 @@ std::string UTMetadataRejectExtensionMessage::getPayload()
 {
   BDE dict = BDE::dict();
   dict["msg_type"] = 2;
-  dict["piece"] = _index;
+  dict["piece"] = getIndex();
   return bencode::encode(dict);
 }
 
 std::string UTMetadataRejectExtensionMessage::toString() const
 {
-  return strconcat("ut_metadata reject piece=", util::uitos(_index));
+  return strconcat("ut_metadata reject piece=", util::uitos(getIndex()));
 }
 
 void UTMetadataRejectExtensionMessage::doReceivedAction()
diff --git a/src/UTMetadataRequestExtensionMessage.cc b/src/UTMetadataRequestExtensionMessage.cc
index 0093fe53..e9e2e1f8 100644
--- a/src/UTMetadataRequestExtensionMessage.cc
+++ b/src/UTMetadataRequestExtensionMessage.cc
@@ -59,13 +59,13 @@ std::string UTMetadataRequestExtensionMessage::getPayload()
 {
   BDE dict = BDE::dict();
   dict["msg_type"] = 0;
-  dict["piece"] = _index;
+  dict["piece"] = getIndex();
   return bencode::encode(dict);
 }
 
 std::string UTMetadataRequestExtensionMessage::toString() const
 {
-  return strconcat("ut_metadata request piece=", util::uitos(_index));
+  return strconcat("ut_metadata request piece=", util::uitos(getIndex()));
 }
 
 void UTMetadataRequestExtensionMessage::doReceivedAction()
@@ -75,27 +75,29 @@ void UTMetadataRequestExtensionMessage::doReceivedAction()
   if(!attrs.containsKey(bittorrent::METADATA)) {
     SharedHandle<UTMetadataRejectExtensionMessage> m
       (new UTMetadataRejectExtensionMessage(id));
-    m->setIndex(_index);
+    m->setIndex(getIndex());
     SharedHandle<BtMessage> msg = _messageFactory->createBtExtendedMessage(m);
     _dispatcher->addMessageToQueue(msg);
-  }else if(_index*METADATA_PIECE_SIZE <
+  }else if(getIndex()*METADATA_PIECE_SIZE <
            (size_t)attrs[bittorrent::METADATA_SIZE].i()){
     SharedHandle<UTMetadataDataExtensionMessage> m
       (new UTMetadataDataExtensionMessage(id));
-    m->setIndex(_index);
+    m->setIndex(getIndex());
     m->setTotalSize(attrs[bittorrent::METADATA_SIZE].i());
     const BDE& metadata = attrs[bittorrent::METADATA];
     std::string::const_iterator begin =
-      metadata.s().begin()+_index*METADATA_PIECE_SIZE;
+      metadata.s().begin()+getIndex()*METADATA_PIECE_SIZE;
     std::string::const_iterator end =
-      (_index+1)*METADATA_PIECE_SIZE <= metadata.s().size()?
-      metadata.s().begin()+(_index+1)*METADATA_PIECE_SIZE:metadata.s().end();
+      (getIndex()+1)*METADATA_PIECE_SIZE <= metadata.s().size()?
+      metadata.s().begin()+(getIndex()+1)*METADATA_PIECE_SIZE:
+      metadata.s().end();
     m->setData(std::string(begin, end));
     SharedHandle<BtMessage> msg = _messageFactory->createBtExtendedMessage(m);
     _dispatcher->addMessageToQueue(msg);
   } else {
     throw DL_ABORT_EX
-      (StringFormat("Metadata piece index is too big. piece=%d", _index).str());
+      (StringFormat
+       ("Metadata piece index is too big. piece=%d", getIndex()).str());
   }
 }