Funded Program in ME21N with Account Assignment Category equal BLANK

Hi

I am doing one ME21N (create purchase order) with Account Assignment Category equal BLANK " ". In u201Caccount assignmentu201D the system only allow to fill the fields u201Cfunds centeru201D, and the u201Ccommitment itemu201D but as the purchase is to INVESTMENT I need to fill the field FUNDED PROGRAM too. I haven´t internal order (CO) and project (wbs element) to do one derivation in this point of process (these objects will be create during the business process). I have already tried to use the fields of FMDERIVE´s trace but unfortunately any combination help me to define the Funded Program.

thanks,

Claudio