anchor.diff:  procedure TBufferedTransportImpl.Open;
   begin
     FTransport.Open
  +  InitBuffers;  // we need to get the buffers to match FTransport substreams again
   end;
   
   function TBufferedTransportImpl.Read( const pBuf : Pointer; const buflen : Integer; off: Integer; len: Integer): Integer;
  
positive.code: begin
    Result := (FWriteBuffer <> nil)
          and (FReadBuffer <> nil)
          and (FStream <> nil);
  end;
  
  procedure TBufferedStreamImpl.Open;
  begin
    // nothing to do
  end;
  
  function TBufferedStreamImpl.Read( const pBuf : Pointer; const buflen : Integer; offset: Integer; count: Integer): Integer;
  
negative.code:   Create( ATransport, 1024 );
  end;
  
  constructor TBufferedTransportImpl.Create( const ATransport: IStreamTransport;  ABufSize: Integer);
  begin
    inherited Create;
  