Reproducible on both trunk and enwikipedia.
Steps to reproduce:
*Have some thingy thats not a redirect in the file namespace.
*Make it a redirect to some other file
*Go in the history, and look at the old (non-redirect) revision of the page.
*You see the old version
*You see the this page is a redirect thingy, for even the non-redirect old versions.
ImagePage.php overrides how redirects are displayed to user, and does it differently then how its normally done. Presumably there is better handling for this in Article.php. With only looking at the code for about 5 seconds, it seems like there should be a better way to do this without the duplication.
I think T29857 has the same root cause.
Relevant example on 'pedia: http://en.wikipedia.org/w/index.php?title=File:Bierstadt_Albert_Lower_Yellowstone_Falls.jpg&action=history
Issue originally reported by Chzz on irc.