https://bugs.winehq.org/show_bug.cgi?id=52969
--- Comment #1 from Gabriel Ivăncescu gabrielopcode@gmail.com --- This looks like it uses jscript behavior for some reason. It might be a bug in the updated Win8, but since it's locale stuff, which doesn't have to be consistent, who knows.
I think the best fix is to simply skip the tests in such case, I'll send a patch.