This code depends on code introduced into the developement branch for
PHP 4.3, so it will not run with PHP releases before 4.3.0

preliminary documentation is available in the dav.txt file,
although it is currently a little outdated ...

Server/Filesystem.php contains a sample implementation for a simple
file server (including property and lock info storage in a mySQL
database, see db/Fileserver.sql). This sample should give you a good 
clue about how to use this class for your own purpose.