Maint Expense Budgeting througg Statistical Internal order

Friends,

We are using statistical internal order budgeting purpose. We made internal order field mandatory for Account assignment category u2018Ku2019.

There is a requirement of budgeting maintenance expenses which have account assignment category u2018Fu2019 (used for Main. Order).

Do we have any option where I can provide account assignment Maint. order as well as Internal order (Statistical) for purchasing documents/ or any workaround for this situation.

Thanks in advance.

Om Tiwari