Down payment

Dear all,

We have configured downpayment settings (through sale order) where everything is working

as per requirement but system is allowing for final invoice (closing)

without downpayment received (through F-29).We want a restriction where

if complete downpayement is not received from customer (downpayment

posted through F-29) delivery and final invoice (F2) should not happen.

Plz suggest any standared settings are available in SAP.

regards,

sp shukla