We have one Project with two sites. The Project was created from a Customer Order with an External Customer.  After running PMRP, Site 1 has a Purchase Order for the Internal Supplier (Site 2). The purchase order line is connected to the Project Activity. Using Inter Site functionality, we released and sent the Purchase Order to the Internal Supplier (Site 2), which automatically created the Customer Order for Site 2 (with Site 1 as a Customer). 

However, the internal Customer Order lines cannot connect to the Project Activity.  We receive this error. Can Inter site POs and CO be connected to the same Project?