Displaying Error message in Call transaction method

Hi Experts,

                  I have some customized transaction if i click on one push button on that transaction . it automatically fill all the screens of standard transaction.though BDC  CALL TRANSACTION METHODi done it.but my problem is

1-> when i put Display mode as 'N' it doesn't  dispaly's any error message even some error occurs in screen's.

2-> when  i put Display mode as 'E' it displays error screen.

but my requirement is if any error occur I want to display error message only in my customized transaction .  i don't want to display the error screen's.so that user authorized to make  changes the flat file only but not in screens.can anyone give solution for this.

                                                                                                                                                                           Thanks in advance.