[ic] Hard Core customization

[Mark Lehrer]

I am trying to have IC call a shell script during the invoice
generation to create an activation key which will be a part of the
email copy that goes out to the user.  I've read all of the
documentation that is included, but I haven't been able to find a
mention of this kind of customization.

Could someone give me a brief idea of what would be the most
"correct" way to do this?  I'm very good with Perl and could probably
go in and hack things up but I wouldn't want to do something that
would just disappear next time I do an upgrade.

Please CC me directly if at all possible!  Thanks in advance,
Mark Lehrer