Does anyone know how to setup a partial subversion mirror?

Essentially we have a source code tree, containing various subdirectories, including doc, test, src/tld/domain and src/experimentalcode/usernames.
We’d like to allow public access to the main source subtree, while not exposing the various user directories to the web server (the master subversion is separate anyway; since I want to use Trac I need a local SVN copy!)

I’m currently trying to setup “tailor” to do this, but it is not trivial: it seems easy at first to just ignore any change in a particular folder. But when you encounter “move” aka “rename” operations that rename a file from the non-exposed folder to the exposed folder, they will obviously fail on the “stripped” repository. So they need to be mapped to an “add” operation there!

Any hints? I might have it working using some hacks in tailor, but I’d like to know any simple solution, if there is any …