AP PO Reconciliation Report and RMAs

I have to correct the AP PO Reconciliation Report so that it ties to the GL balance for the PO Receipt Accrual Account. One of the issues I am confronting is that when an RMA is issued against a PO that has been paid, the PO reappears on the report. With the uninvoiced receipts report the the transaction disappears once it has been paid and stays off the report, with the AP PO Accrual Report the RMA causes the PO to reappear. Can anyone tell me why this is happening. Even if we close the PO line, the transaction still