cleanest way to maintain 'my hacks on packages' in pkgsrc

[George Michaelson <ggm%apnic.net@localhost>]

I love igal. its in wip/igal. But, I want to hack on it, to make the
installed template be "my" template, and change some icon behaviours.

Its already frozen code (I asked the author, no dev since 2003)

Its already accreted some useful hacks in patches/

forking can be evil, but driving "my" hacks into patches/ is really
overkill.

So, do we have a generalized model of how to make a mini-hack pkg which:

        1) depends on the base pkg and/or CONFLICTS with it somehow
                depending on what makes sense

        2) overloads it with localized patches I own

        3) could be shared via wip or other pkgsrc if useful

I'm thinking a pkgsrc/localhacks/<thing> hierarchy which is in
the .cvsignore, so it doesn't freak my updates.

What do other people do?

-G