Was seeing a whole lot of:
Expired <em class="placeholder"></em> stale files from static page cache. in my logs coming from http://default/index.php on cron runs.
Did a small amount of debugging; turns out $_boost['base_dir'] in boost_cron() was returning a value of
path/to/boost/normal/default, but Boost was saving off cached files in
I was able to get around the problem by manually setting the $base_url to
http://www.example.com in settings.php.