Receivables - Refund Application

Hi,

does anyone know if the following is possible:

we have an unusual requirement where we would like to partially refund a receipt to a different customer.

e.g.

Receipt R001, Customer C1, Amount 1000

- Apply 600 to transaction as normal.

- From the Application screen refund 400 for Customer C2.

is it possible to allow this, i am fairly certain it is not, but would like confirmation before i examine best alternatives fully.

thanks.

Brian