Purchase Orders approved by an ex-employee

Hi,

We are working on Oracle Applications 11i. In Oracle Purchasing we are using the position  approval hierarchy to approve purchase orders.

One of the approvers has approved 2 Purchase orders after he was  terminated by the HR ; he was an ex-employee in his Oracle HR record and the employee was leaving the company.

A request was made to reactivate the employee and assign him to the old position.

But still we cannot find those 2 POs in the forward documents - management window.

Any Ideas???