regading ok_code in dialog programming?

Hi frnds,

my problem is in my screen the ok_code is nt cleared.

In my screen 100 i declared the BACK ,EXIT and CANCEL. and then in de same screen i called a dialog screen103 and given BACK ,EXIT and CANCEL for the dialog screen.

Now the problem is wen i cancel that dialog box it is gng but when i operate BACK to screen 100 again the dialg box is cmg.

here ok_code is nt clear.

Can any one help how to clear the ok_code ........?

thanks in advance.