I’m using Boulevard on a Danish website, set up with a Danish date format "18. februar" in WordPress.
For some reason Boulevard insists on showing this with the Danish spelling but in the wrong order as "Februar 18" everywhere, including the front page.
See www.av-blog.dk for examples.
you have to find every instance of the_time(‘F d, Y’); in your files and change them to your desired format. You can find a reference here: http://codex.wordpress.org/Formatting_Date_and_Time.
e.g. line 27 in index.php and so on