2009/4/14 Joe Atzberger <ohiocore@gmail.com>:
The implementation for "targeted" payments was buggy and error-prone, at best, mainly because there was no unique key on the accountlines table. It resorted to an imprecise and slow subqueries try to generate the desired effect, and it wouldn't scale. So for now you can only pay against your balance.
Bummer, in the olden days it used the accountoffsets table, with borrowernumber and accountno as the key. And you could select the charge(s) you wished to pay. Then It got changed to just use accountlines and I suspect thats where the bugginess came in.
This should be resolved either by the recent patches to make accountlines editable, and more broadly, by Ryan's overhaul of fines.
Excellent to both Chris