I'm building a multisite with blogs in different languages; theme ist twentytwelve. Here's the problem: The german subblog shows english messages, though the language files delivered with the theme are there in the "languages"-directory. The subblog is set to "german" in the Blog-settings.
This problem seems to occur only with multisites, in non-multisite use the language files work fine. I tried with theme twentyeleven, it's the same.