Web translation was done considering that if you were browsing in a language and you go to a page not translated, the English version would appear.
The bad thing of this approach is that when you go are in an untranslated English page, as it is not in another language, you do not have the chance to go the original language.
An option I was thinking about was to change the behavior. If a page in another language does not exist, uppweb would clone the English version adding a thin footer indicating that the page is not translated and inviting to translate it.
This would have exceptions like Forum. These would be managed directly by the code that would not add a header.