how should I prepare a link like [[:en:UTF-8|UTF-8]] with tvar ?
The easy way is [[<tvar|link>:en:UTF-8</>|UTF-8]], I guess.
But it would be better if the link would lead to the localized wikipedia
article if it does exist, but fallback on the original otherwise. Such a
behaviour is in fact rather tricky to perform, and I'm little stuck
there, trying to misc. combination of "{{#translation:}}" and
"Special:MyLanguage/". Maybe some magic keyword jedi master might help
here? :)