Email notification is not send to supplier after PO is created with Import Standard Purchase Orders

Hi,

I am creating a Purchase Order with Import Standard Purchase Orders Concurrent. The Approval Status Parameter is set to Approved . The PO is created and after a few minutes the PO is approved, but Email notification is not send to supplier.

In the vendor at site level I set Notification Method "Email" and in Email field I put a valid email.

Please... I need Help... Any Idea why email notification is not send?

Thanks

Grigerlis