For non-latin languages it's problem to use URL of MediaWiki pages. For example, article with name "Список языков с алфавитами на основе кириллицы" (List of languages using Cyrillic alphabet) has ugly URL:
http://ru.wikipedia.org/wiki/%D0%A1%D0%BF%D0%B8%D1%81%D0%BE%D0%BA_%D1%8F%D0%...
Opera browser auto decodes this URL to readable link: http://ru.wikipedia.org/wiki/%D0%A1%D0%BF%D0%B8%D1%81%D0%BE%D0%BA_%D1%8F%D0%...
In Firefox it's able to use HumanURL extention, but in IE it's problem.
So can I add option "wgEncodeUrlsInUtf8" to LocalSettings.php and check it in function wfUrlencode in GlobalFunctions.php? (to turn off PHP urlencode function)
See also http://en.wikipedia.org/wiki/Internationalized_Resource_Identifier
you can see demo of the hack at http://mediawiki.jino-net.ru/index.php/Main_page
Discussion in Russian: http://community.livejournal.com/ru_wikipedia/24808.html
-- Alexander Sigachov http://meta.wikimedia.org/wiki/user:ajvol