Well, following Welterweight's suggestion in this thread, I'd like to start a post about this.
Currently the dates in the goldlog seem to be returned by the OS (possibly the browser too but I haven't confirmed this).
When someone changes the language settings on the forum he/she usually expects goldlogs to have that language.
Changing the language your date is showing in the OS is required (and probably shouldn't) in order to make the logs show appropriate dates. It's a small issue, really, but it does seem to especially affect people who are using the forums on any language and have other date language settings (not the same as OS language) in their computers since they are not in a location where the language the forum is set to is spoken.