new partner function

Hi,

I have created a new partner function" goods supplier" and I want to build a table for pricing dependent on that new partner function. Goods supplier is entered manually in a sales order.

I can not add this field to the field catalogue of allowed fields for pricing , because there is no such a field.

Do I have to create a new field ad add it to the structures KOMG, KOMK or KOMP ?

Please explain how to proceed?

Regards

Dominik