New pricing with delivey date on the invoice

Hi,

1) My sales order document currency = ILS.

ItemCondCurr Item CondPricingDate Exchange Rate Item Quantity

EUR 10.08.2008 5,15000 100

2) I am creating three delivery for the sales order.

First delivey date = 08.09.2008 Exchange Rate = 5,18 on the system

Second delivery date = 09.09.2008 Exchange Rate = 5,19 on the system

Third delivery date = 10.09.2008 Exchabge Rate = 5,2 on the system

3) I am creating delivery related three invoice.

I must take to new exchange rates with delivery dates for new pricing.

What can I do?

Thanks

Gulay Celik