Prepayment receipt application

Hi

I am trying to use Prepayments in receivables linked directly to a Project. Ideally when I create an Invoice in project and interface it to receivables it should automatically match the invoice to the prepayment receipt but it is not exactly happening.

The system does triggers the prepayment matching program after the Auto Invoice completes but it doesn't matches the prepayment receipt to the invoice. Can some one point out why this is happening or shall I raise an SR with oracle?

Regards,

Nilesh