Best way to update item descriptions without data discrepancy

Hi All, we have a requirement wherein we have to update the item description on a lot of our cataloged item (services, stock, non-stock). As per standard functionality whenever we update the item description all existing PO's (both open & closed) also get updated if the 'Allow Description Update' flag is unchecked. We feel this is not a good functionality introduced by Oracle because the historical PO's should not be updated as they are legal documents already issued out to vendors. Also, in such a scenario only the existing PO's are updated with the new item description and the requisitions/releases/invoices