hg convert がうごかないんだが、なんでかな?
% hg convert -s svn svn://svn.freebsd.org/base
assuming destination base-hg
initializing destination base-hg repository
Subversion python bindings could not be loaded
abort: svn://svn.freebsd.org/base: unknown repository type

% hg convert -s svn freebsd-head
assuming destination freebsd-head-hg
initializing destination freebsd-head-hg repository
Subversion python bindings could not be loaded
abort: freebsd-head: unknown repository type