Overpayment of invoices (not as an advance on future invoices)

[Robert Heller]

What is the best way to deal with the case where a customer pays an
extra amount over the invoice, not as an advance payment for a future
invoice but as a kind of gratuity?  If I do a process payment of the
amount of the payment, gnucash will create a credit that will be
applied to the next invoice -- I don't want to do this, since this is
not the customer's intent of the extra payment.  I would *like* to have
one transaction/split, rather than do a process payment for the amount
of the invoice and then entering a *separate* transaction for the excess
(as raw, non-invoiced, income).

-- 
Robert Heller             -- 978-544-6933 / heller at deepsoft.com
Deepwoods Software        -- http://www.deepsoft.com/
()  ascii ribbon campaign -- against html e-mail
/\  www.asciiribbon.org   -- against proprietary attachments