Between OpenOffice.org 3.0 release and 3.2 release Subversion was used as the source code repository.
After the 3.2 release OOo has migrated to Mercurial. Now the subversion repository is only useful for getting the sources of the OOo 3.1 release branch (OOO310).
For current information on how to build OOo, see the OOo Wiki: Building Guide
svn checkout svn://svn.services.openoffice.org/ooo/trunk
or
svn checkout http://svn.services.openoffice.org/ooo/trunk
Point your browser to
http://svn.services.openoffice.org/ooo
Write access to the repository requires a ssh setup.
svn co svn+ssh://svn@svn.services.openoffice.org/ooo/trunk
svn checkout http://svn.services.openoffice.org/ooo/tags/DEV300_m35
svn checkout http://svn.services.openoffice.org/ooo/cws/foo