Some pages containing an interwikis to zh-classical show this interwiki link as zh-classic prefix (without -al). I think this i because the database field was shorter in the past.

For http://zh.wikipedia.org/wiki/Template:Link_FA the api returns:
lang="zh-classic"
url="http://zh.wikipedia.org/wiki/Zh-classic:Template:Link_FA"

using query http://zh.wikipedia.org/w/api.php?action=query&prop=info|langlinks&titles=Template:Link%20FA&lllimit=max&llurl

But http://zh.wikipedia.org/wiki/Zh-classic:Template:Link_FA is not correct because it is a valid title in article namespace on zhwiki.
For interwiki bots it shows an languagelink to the same site which must not be possible because self links are not permitted per definition (that why [[zh:abc]] on zhwiki is parsed as interwiki and not an languagelink)

There is no prefix zh-classic on interwikimap http://zh.wikipedia.org/w/api.php?action=query&meta=siteinfo&siprop=interwikimap

So please update languagelink table so that api can return valid values.

Version: unspecified
Severity: major