README currently says

Check out the mmd-schema and search_server repositories using Subversion as follows:
svn co http://svn.musicbrainz.org/mmd-schema/trunk mmd-schema
svn co http://svn.musicbrainz.org/search_server/trunk search_server

whereas it should point to github.com mmd-schema in order to build the project

git clone https://github.com/metabrainz/mmd-schema.git
svn co http://svn.musicbrainz.org/search_server/trunk search_server

as detailed in http://wiki.musicbrainz.org/Development/Search_server_setup#Download_the_search_server_and_schemas