Well, actually, I think that whole webapps structure in gentoo should be
dropped or totally rewritten, despite of web applications packages state in
the gentoo repo.
It is unextendable, uncomfortable, no-gentoo-way'ish and so on.
I think, it would even be better to just install apps in /usr/share/${PF} than
current webapp behaviour.
And, talking ontopic, I think let it (postfixadmin) be dropped.
Anyone interested (like me) will just fetch tarballs directly from upstream,
and upgrade in usual way, without webapps black magic and sacrificing virgins.