How to change confirmed quantity in shedule lines of sales order?

Hi Experts,

         i have gone through the SDN for chage confirmed quantity but i couldn't trace it.

         So please suggest me how to change confirmed quantity at schedule lines of sales order.

          i have gone through the Bapi's : BAPI_SALESDOCUMENT_CHANGE

                                                         BAPI_SALESORDER_CHANGE.

          please help me.

Thanks & Regards,

Dinesh.K