[FI] ABAP_add new colunms to FBL*N
 Please follow these steps:      Step1.  Add new fields in the structure RFPOS;       Step2.  To fill your new fields you active the BTE 1650:     you have to copy the fm SAMPLE_INTERFACE_00001650 and here insert abap code to fill the new fields.     By trx FIBF: Setting->Event: here insert the name of your fm for event 1650.       Step3.  Run the report RFPOSXEXTEND: this report will arrange the structure RFPOSXEXT based on definition of RFPOS.     Remember this modifications are available  for all kind of items: so G/L (trx FBL3N) , Receivable (trx FBL5N) and Payable FBL1N.     So in your fm check the field KOART:     KOART = 'S' ->G/L   KOART = 'D' ->Payable   KOART = 'K' ->Receivable