Can adhoc approvers be added at the beginning of an approval workflow

Hi,

We have a custom workflow for PeopleSoft vouchers (2 way PO). As per the setup, the voucher goes to the requester first( Step criteria type always True). The user is requesting an adhoc approver be added to the workflow at the beginning. I have found that the voucher is always routed to the requester as the first approver. The Approval Monitor gives the admin to add an ahoc approver at the last. In general, is it possible to add an adhoc approver at the beginning ?

Thanks,

Debolina