Recovery at the time of payment

Hi All,

In eBusiness Tax, i understand that the tax can e set for recovery as follows

Standard: Recovered at the time of invoicing.

Deferred: Recovered at the time of actual invoice payment. Though at the time of invoicing the recovery entry is parked into an "Interim tax" Account, it is at the time of payment that it is passed to actual recovery account.

My requirement is to have the recovery entry passed only at the time of payment. My receovery rate changes on a monthly basis and if invoice is accounted in one month and payment is made in subsequent month, i want the tax to be recovered at the rate at the time of payment.