This has come up from a couple of different clients in the last few weeks. It would be good if approval workflows could be added to Receivings Transaction Entry and also the Enter/Match Invoices windows.
While there is workflow on the PO, a PO might not be fully received/invoiced so it would be good to have approval of the receivings document or the invoice.
The MS Connect suggestion can be found here.
Please take a look and cast your vote.