diff --git a/ChangeLog b/ChangeLog
index 3e8c6b5b..56714d25 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2008-05-15  Tatsuhiro Tsujikawa  <tujikawa at rednoah dot com>
+
+	Defined fake filename `[tracker.announce]' as static const std::string.
+	* src/TrackerWatcherCommand.cc (createRequestGroup)
+
 2008-05-15  Tatsuhiro Tsujikawa  <tujikawa at rednoah dot com>
 
 	Defined default filename `index.html' as static const std::string
diff --git a/src/TrackerWatcherCommand.cc b/src/TrackerWatcherCommand.cc
index 537ca385..ba775274 100644
--- a/src/TrackerWatcherCommand.cc
+++ b/src/TrackerWatcherCommand.cc
@@ -174,11 +174,12 @@ TrackerWatcherCommand::createRequestGroup(const std::string& uri)
   uris.push_back(uri);
   RequestGroupHandle rg(new RequestGroup(e->option, uris));
 
+  static const std::string TRACKER_ANNOUNCE_FILE("[tracker.announce]");
   SingleFileDownloadContextHandle dctx
     (new SingleFileDownloadContext(e->option->getAsInt(PREF_SEGMENT_SIZE),
 				   0,
 				   A2STR::NIL,
-				   "[tracker.announce]"));
+				   TRACKER_ANNOUNCE_FILE));
   dctx->setDir(A2STR::NIL);
   rg->setDownloadContext(dctx);
   SharedHandle<DiskWriterFactory> dwf(new ByteArrayDiskWriterFactory());