add_action( \'init\', \'wpa_category_base\' );
function wpa_category_base() {
    // Remember to flush the rules once manually after you added this code!
    add_rewrite_rule(
        // The regex to match the incoming URL
        \'news/([^/]+)/([^/]+)/([^/]+)(/[0-9]+)?/?$\',
        // The resulting internal URL
        \'index.php?category_name=$matches[1]/$matches[2]&name=$matches[3]&paged=$matches[4]\',

        // Add the rule to the top of the rewrite list
        \'top\' );
}

为我工作，WordPress 3.4.1，没有任何相关插件。

尝试

add_action( \'init\', \'wpa_category_base\' );
function wp_category_base() {
// Remember to flush the rules once manually after you added this code!
    add_rewrite_rule(
    // The regex to match the incoming URL
    \'news/([^/]+)/([^/]+)/([^/][^f][^e][^e][^d]+)(/[0-9]+)?/?$\', //here my changes to exclude \'feed\'
    // The resulting internal URL
    \'index.php?category_name=$matches[1]/$matches[2]&name=$matches[3]&paged=$matches[4]\',
    // Add the rule to the top of the rewrite list
    \'top\' );
}