[Koha] Paying fines (again)?

[George Adams]

(Koha 3.0alpha, (Gentoo) Linux 2.6.24, MySQL 5.0.56)

I appreciate all the help over the last few months.  We're about launch
our little library here at church, but I just wanted to try this
question once more:

Is there any way to have Koha tell the librarian, either during a
check-out or check-in, that the current patron has a fine on his
account?

If it's a check-in, the patron may want to pay the fine right away.
If it's a check-out, we want to disallow the checkout (no further
borrowing until the fine is paid).

I'm sure there are existing Koha sites that do this kind of thing,
right?

Thanks again.