in Page A4 duplex print is working, but fails on page:custom, how can I fix it ? thanks!

wilson631016

procedure TduplexTest_frm.Button1Click(Sender: TObject);

var A:TfrxReportPage;

idx:integer;

begin

 idx := printer.Printers.IndexOf(PrinterName);

 if idx = -1 then

 begin

  showmessage(PrinterName + ' can''t find printer');

  exit;

 end;

 rpt.PrintOptions.Printer := PrinterName;

 a := rpt.FindObject('page1') as  TfrxReportPage;

 // DuplexMode := dmVertical;

 a.Duplex := dmVertical;

 rpt.PrintOptions.Duplex := dmVertical;

 ds.RangeEnd := reCount;

 ds.RangeEndCount := length(buff);

 if rpt.PrepareReport then

  rpt.Print

end;