Sorting F110 Printout by Vendor and Line Items.

Folks,

How can I sort the Payment prinouts from t-code F110 by Vendor and Line items.

I tried looking at RFFORI01 but there is no place where I can sort and rearrange the

items so that one page prinout will be printed first and multi page printouts later.

I know I can copy RFFOUS_C to Z program and do changes but where to do

the sorting logic.

I tried looking at FBZP Transaction but in vain.

Your help is appreciated