Index: trunk/Include/Classes/System/IO/FileStream.ab
===================================================================
--- trunk/Include/Classes/System/IO/FileStream.ab	(revision 429)
+++ trunk/Include/Classes/System/IO/FileStream.ab	(revision 430)
@@ -451,9 +451,5 @@
 Protected
 	Override Function CreateWaitHandle() As System.Threading.WaitHandle
-		'調査した限りでは、System.Threading.EventWaitHandleクラスをNewする模様。
-		'現状ではSystem.Threading.WaitHandleクラスをNewしてからHandleにて設定
-		Dim wh As System.Threading.WaitHandle
-		wh.Handle=CreateEvent(NULL,TRUE,FALSE,NULL)
-		Return wh
+		Return New System.Threading.AutoResetEvent(False)
 	End Function