hi hans & all,
i am working on a small software with wxwidgets and came across a solution for updating the package, the software or the updater via http. it's cross platform and very flexible to my eyes. i am just proposing this solution for pd-extended, that way people who wants to upgrade, just need to launch the "web update" (listing the externals that are new, updated, documentation etc...).
http://wxcode.sourceforge.net/docs/webupdate/
i am sure there's other open source solution out there. pat