Andrea,
I've been researching this, and have some specific questions.
I understand that I'd need to install the Traditional Chinese (zh_TW) language pack. I've downloaded .mo and .po files from the 2.9 branch from http://svn.automattic.com/wordpress-i18n/zh_TW/branches/2.9/messages/, and installed them in my wp-includes/language folder.
However,
1. I'm not sure what you mean by 'Choose the language for that blog in backend'. From the instructions in the codex, it would seem I'd have to edit the wp-config.php file, and change the WP_LANG variable with:
define ('WPLANG', 'zh_TW');
but that would change the language for *all* of the blogs, wouldn't it? Can you clarify what steps are needed for this? I only want
that for one blog.
2. After this change is done, all text (i.e. not just user content, but wordpress itself) for the one Chinese blog will have Chinese characters, correct? I realize I may have to refresh my browser and maybe clear my cache.