diff --git a/websocket-sharp/Net/RequestStream.cs b/websocket-sharp/Net/RequestStream.cs
index 1a4e3f8a..6e5945c3 100644
--- a/websocket-sharp/Net/RequestStream.cs
+++ b/websocket-sharp/Net/RequestStream.cs
@@ -180,7 +180,7 @@ namespace WebSocketSharp.Net
       }
 
       if (count == 0)
-        return _stream.BeginRead (buffer, offset, count, callback, state);
+        return _stream.BeginRead (buffer, offset, 0, callback, state);
 
       var nread = fillFromBuffer (buffer, offset, count);