Say, with the default interwiki.sql, do links to non-English Wikipedias always need to be routed thru the English Wikipedia, [[wikipedia:zh:跨性別]]: (the only example format on http://meta.wikimedia.org/wiki/Help:Interwiki_linking that worked on my home wiki.) http://en.wikipedia.org/wiki/zh:%E8%B7%A8%E6%80%A7%E5%88%A5 -> HTTP/1.0 302 Moved Temporarily Location: http://zh.wikipedia.org/wiki/%E8%B7%A8%E6%80%A7%E5%88%A5 Or is there a better way that doesn't need WikiSysop's help? (not to mention altering the database or installing extensions.)
Anyway, without a standard to follow, each installation will come up with their own prefixes: ('zhwikipedia', 'http://zh.wikipedia.org/wiki/$1', 1), ('zhw', 'http://zh.wikipedia.org/wiki/$1', 1),