Cannot Query Terminated Buyer's PO'S In PO SUMMARY Window

Hi, All
R: 12.1.3
Steps to reproduce:

1.User HR Function Terminated a buyer.
2.Fill employee hierarchy
3.Cannot Query the Terminated Buyer's PO'S In PO SUMMARY Window.

I found for 11i, there are patches applied. Or workaround.
But I have no patch found available for R12. Ct prefers to apply patch.

Thanks.