Is your feature request related to a problem?

Nope just a suggestion.

What is the feature?

I noticed Textile (or TXP code attached to it) change some typographic signs according to the user language choice within the administration interface (which is very useful).

Because it is extremly easy to create multilingual websites with TXP without the need of any plugins, maybe it will be interesting to add a language selector list into the "Write" tab, according to languages files installed? So, typographic rules could be apply accordingly to the languages.