I think you should avoid using the acronym CMS, because it's been pretty much hijacked worldwide by the Mambo/PHP Nuke/Xoops crowd etc (and this is what
this forum is all about too). Also, technically Moodle is a Course Management System.
Let's just stick to "Repository" or "DMS" to avoid confusion.
On that note, how many Repositories are out there that actually support JSR-170 today? And are there any in PHP yet?