One Workflow Notification

Hello,

I'm using the standard Workflow WS20000075 to validate the Purchase Order.

My problem is: The WF send to initiator a notification for each validation ( for each validation level).We don't want that.

We want that the initiator (creator) of PO will recieve just one notification when the PO is completly validated.

Can you tell me how to do that with WS20000075 ?

Thank you in advance.

With Best Regards.