Wine will select the language version of the resource to display basing on user settings. For example "LANG=ru_RU winecfg" will launch winecfg in Russian (if you have Russian locale information installed in Linux/your other native system).
I have tried this. However, it has never worked for me; Wine just completely ignores my environment variable. Japanese Windows apps will NOT use the correct encoding to show text correctly, and doing something like "LANG=nl_NL winecfg" doesn't change winecfg or any other application into Dutch. I do have Dutch and Japanese localizations installed on my Ubuntu rig through the distro's Language Support dialog, but it doesn't seem to make a difference...
What seems to be the problem? I'd like to improve Dutch translation, but I can't really test the results like this...
vincent@vincent-eeepc:~$ sudo locale-gen nl_NL.UTF-8
Generating locales...
nl_NL.UTF-8... cannot open locale definition file `nl_NL': No such file or directory
failed
Generation complete.
It's not in locale -a afterwards. Installing language-pack-nl and language-pack-nl-base in Ubuntu's package manager made no difference; in fact, these packages' post-installation triggers are supposed to do this and fail too.
Woops, no edit button. Japanese is missing most of the Kanji, and I've got msttcorefonts and the non-free version of Kochi-Mincho installed... Strange.