var
   Device:Array[0..cchDeviceName-1] of Char;
   Driver:Array[0..(MAX_PATH-1)] of Char;
   Port:Array[0..32] of Char;
   hDMode:THandle;
   pDMode:PDevMode;
begin
     Printer.GetPrinter(Device,Driver,Port,hDMode);
     if hDMode<>0 then
     begin
          pDMode:=GlobalLock(hDMode);
          if pDMode<>nil then
          begin
               pDMode^.dmPaperSize:=DMPAPER_A5;
               pDMode^.dmFields:=pDMode^.dmFields or DM_PAPERSIZE;
               GlobalUnLock(hDMode);
          end;
     end;
end;