Demand Planning an Oracle Engineering item

We have Oracle Engineering and are trying to implement a new item lifecycle.  We have many questions but one of the main ones i am looking for an answer on is "Can we use our demand planning processes to schedule engineering items?  We are having issues if we set up a top level engineering bill of material, that contains both engineering and inventoryitems, that the prototype items are not scehduled if intercompany sourcing rules are set up properly.