http://bugs.winehq.org/show_bug.cgi?id=17936
--- Comment #11 from Steve Rencontre q.winehq@rsn-tech.co.uk 2009-04-07 06:47:39 --- Ah, yes they are different. I thought that by appending .xxx to the filename I was making it invisible to the font engine, not that it was still finding it but not misusing it.
However, when you say it's "broken", it's Microsoft who have broken it. A bit of Googling shows other people having some problems with this version (2.40) purely in Windows, eg,
http://forums.techarena.in/windows-update/967926.htm
It seems to be fixed there too by reverting to the older version (2.35) which is what I've got in webcore, but that's obviously a workaround rather than a solution.
AIUI, the update is part of XP SP3, so if you haven't installed that, it would explain why your Windows version didn't misbehave.