Last modified: 2009-02-04 19:01:51 UTC
Transcluding Special:PrefixIndex in a page affects the page title in that it's apparently renamed to "Prefix Index" (or the localized variant). Maybe some sort of cache issue, since I can't reproduce it on enwiki? On srwiki (see URL), Википедија:Можда користан материјал is the page that transcludes Spec:PI, but the title is Списак префикса (which means Prefix Index). Note that this is in the Project: namespace, so that may mean something.
fixed in r46808.