You might look into docpad, then. Jekyll and others are largely built around blogging, but docpad is more of a framework for writing code to generate static sites. It does a much better job of allowing you to do anything you want, porvided you're willing to write some javascript.
Is there any chance that you know a website with docpad (or anything else) that uses the above archive format? I've sample the showcase/example site, but I was not able to identify any.
You could probably just arrange your posts in src/documents in this format, and let your layout do a lot of work for you such that each of the files in src/documents/<lang> contains little more than the blog text in its respective language.
