I just overhauled the locale/translation system to fallback. Webird 0.5 is now in a (ehm) string freeze while a translator fills out the blank localization files for German, Russian and Ukrainian over the next several days.
The latest code can be seen in action at Webird. Guest registration is currently disabled but you can observe the fancy JS loading mechanism by inspecting the browser console.
Webird now has the beginnings of Russian support and ru, ru_RU and ru_UK all utilize the ru_RU translation. This can be done for any locale and you can customize (map) it if you require greater regional dialect control. Here is the current built-in locale config