I need modular and configurable %posttrans-like scripts.
Examples:
1) automatic run of update-menus, if package has /usr/lib/menu/*
2) update-desktop-database -- /usr/share/applications/*.desktop
3) gtk-update-icon-cache -- /usr/share/icons/hiclolr/*

I mean that, for common tasks, I do not want packagers to write
their %post-like scripts at all.  Simple cache updates should
be handled by rpm itself.

Now, is there somehting like this in rpm5.org, to start looking at?