I have a site that contains English and Traditional Chinese articles (posts) that are UTF-8 encoded.
I found that although the_excerpt() seems to be working with English articles (i.e., displaying the first paragraph or some and then [...]), with the Chinese articles, full text is shown.
I am *guessing* that this is caused by behaviour within the wp_trim_excerpt function in the core wp-includes/functions-formatting.php file.
Namely, the explode function may be does not quite work with UTF-8 encoded Chinese traditional text? It is a shame that at http://www.php.net/manual/en/ref.mbstring.php, there does not seem to be a multibyte version of explode function.
Is this a WordPress Bug? How can I fix it (without hacking the core Word Press files)?