On MediaWiki.org, which has content language as english, if your preferences are in other language or you use the ?uselang=xx parameter to the URL to change the interface language, links to wiki pages that are on non-main namespace, display the link with the namespace in the interface language instead of the wiki's language. That looks very weird.
The link points to the correct page, though. It's just the text of it which is messed up.
For example, perform a search and have some results in pages other than the main namespace. On interface language "pl" it displays links to "Talk:Download from SVN" as "Dyskusja:Download from SVN".