code: protected void sendError( String errText, HttpServletResponse response )
          throws IOException
      {
          sendError( errText, null, response );
      }
docs: Send a Page Flow error to the browser.
  
  @deprecated Use {@link FlowController#sendError(String, HttpServletRequest, HttpServletResponse)} instead.
  @param errText the error message to display.
  @param response the current HttpServletResponse.