The Mobile Web Best Practices checker is composed of a set python modules, available in the W3C public CVS Repository.
This page documents what modules are needed beyond these modules and a working Python 2.3 installation.
To avoid downloading DTD from the W3C server (and although they would be cached), the checker uses the catalog of pre-defined DTDs made available in the Markup Validator: it needs to be checked out from CVS and copied into /usr/local/share/sgml-lib/ (or configured adequately in validity.py).
xmlproc has a bug that affects XML Well-formedness checking; you should apply the suggested fixsys.setdefaultencoding of python to utf-8; in debian, this is done by editing /etc/python2.X/site.py (NB: this affects all your running python code; there must be a better solution, but I'm not sure what it is)/tmp/httplib2-cache which needs to be writable by the scripttemplates directory needs also write-access