This directory contains a Samba VFS module. When used, this module simply passes all requests back to the disk functions (i.e it operates as a passthrough filter) except then it detects an SVN working copy. In that case, it'll SVN commit any changes.
You need a reasonablly new samba source to compile against. I've tested with samba-3.5.4. You also need headers for Subversion and Popt.
On my Ubuntu system:
apt-get install ibsvn-dev libpopt-dev
./autogen.sh
./configure --with-samba-source=../samba-3.5.4/source3 --enable-developer
make
make test
sudo checkinstall