Fund reservation for direct material process in SAP SRM

Hi expert,

For my project I have the following issue.

In SRM 7 with extended classic scenario with ECC 6.04 and without PPS module, my customer require the possibility to put fund reservation fields for direct material process in the Shopping Cart and in the Purchase Order.

In ECC is possibile to put these in the purchasing requisition and in the purchase order, in SRM when the user put the flag ."order ad direct material" account assignment category will be missed.

Can you explain any possibile solution for my question?

Thanks in advance for your feedback.

Best Regards