Hi. I'm the current maintainer of WWW::Wikipedia. I can tell you that the results from wikipedia have been slightly odd of late on the language front.
I recently released version 2.01 because our language test was failing -- trying to grab the english page for "Russia" then grabbing the russian version. The languages returned were no longer as expected.
As far as "Rotation" goes. Here is what we parse: http://en.wikipedia.org/w/index.php?title=Rotation&action=raw
as you can see, there are no language links in the stream. Perhaps we should send an inquiry to wikipedia/wikimedia on the matter?