Now, hasn't anybody thought in doing it as javascript at user side?
So it works in Russian Wikipedia
"Wikificator" is a JavaScript currently used in the Russian Wikipedia. It is embedded in the source code of an edit page, so that any visitor can use it just by clicking a link below their editing box. The script applies certain transformations (mainly regarding typographics, such as dashes, quotation marks, etc) to text highlighted in the editbox, if any; otherwise to the whole article. It is very convenient and does a great job improving the look of the Russian Wikipedia's articles. Thw script can be modified only by our sysops, since it sits MediaWiki namespace.
Note that the Russian typographical conventions are quite different to the Anglo-American ones.
The script http://ru.wikipedia.org/wiki/MediaWiki:Wikificator.js Description http://ru.wikipedia.org/wiki/%D0%92%D0%B8%D0%BA%D0%B8%D0%BF%D0%B5%D0%B4%D0%B...
Example
Befor
Text text "text in quotation marks "nested" text" - mdash.
After
Text text «text in quotation marks „nested" text» — mdash.
-- Alexander Sigachov