We've invested some time into using the Translations app for our old-style FBML facebook apps. The creation of FBML apps is now deprecated, and only iFrame apps can be created. We would like to have translations in them too, and are considering how to use the Translations app to achieve this.
The internationalization page indicates translations are renderable through (deprecated) FBML tags like fb:intl. It also mentions that XFBML tags (the "newer" tag-set parsed by JavaScript) can play a part, however the documentation for the JavaScript FB.XFBML.parse(..) XFBML method doesn't list any XFBML internationalization tags available to be used with it!
In short, I would like to know if we can use the Facebook Translation app for translations inside an iFrame app, without using any deprecated technology?
[The state of facebook, May 2011]