I'm currently working on a interwiki bot and it happens i gets some intewikis duplicated, some wikis refers to en:City while others to en:Town, etc. But the zh interwikis are the worst as there is not only that kind of problems but up to 3 ways to link with 'http://zh.wikipedia.org/wiki/$1': zh, zh-cn, zh-tw. And there is also zh-min-nan for 'http://zh-min-nan.wikipedia.org/wiki/$1'.
What i have found is that zh means (Zhong Wén) - Chinese, zh-cn Simplified and zh-tw traditional. However they all link to the same place. So what's the preferred option? Should zh-cn/zh-tw links converted to zh links? Should they 3 stay even if they link to the same page? How could a bot know if a page should be referred as simplified, traditional...? Is any meta: page explaining this? (if so, where?, as i haven't found). Should i better simply disable zh* to be recognised as interwikis?
Thanks in advance.