http://bugs.winehq.org/show_bug.cgi?id=14901
--- Comment #19 from redneb@gmx.com 2009-03-14 15:16:41 --- (In reply to comment #18)
(...) wine already deals with files in a case insensitive way (...)
That's where the problem is. Windows has case insensitive filename semantics but MoveFile is case sensitive in some ways. So I wouldn't be surprised if someone fixes your test case but the problem is still there. On the other hand, I don't really know much about the internals of wine so I might be mistaken.