Wordpress 2.5.1 500 错误解决方法

<?php
......
if ( 'draft' != $post_status ) {
    $post_name_check = $wpdb->get_var($wpdb->prepare("SELECT post_name FROM $wpdb->posts WHERE post_name = %s AND post_type = %s AND ID != %d AND post_parent = %d LIMIT 1", $post_name, $post_type, $post_ID, $post_parent));

    if ($post_name_check || in_array($post_name, $wp_rewrite->feeds) ) {
        $suffix = 2;
        do {
            $alt_post_name = substr($post_name, 0, 200-(strlen($suffix)+1)). "-$suffix";
            // expected_slashed ($alt_post_name, $post_name, $post_type)
            $post_name_check = $wpdb->get_var($wpdb->prepare("SELECT post_name FROM $wpdb->posts WHERE post_name = '$alt_post_name' AND post_type = '$post_type' AND ID != %d AND post_parent = %d LIMIT 1", $post_ID, $post_parent));
            $suffix++;
        } while ($post_name_check);
        $post_name = $alt_post_name;
    }
}

<?php
......
/**
 * Prepares a SQL query for safe use, using sprintf() syntax
 */
function prepare($args=NULL) {
    if ( NULL === $args )
    return;
    $args = func_get_args();
    $query = array_shift($args);
    $query = str_replace("'%s'", '%s', $query); // in case someone mistakenly already singlequoted it
    $query = str_replace('"%s"', '%s', $query); // doublequote unquoting
    $query = str_replace('%s', "'%s'", $query); // quote the strings
    array_walk($args, array(&$this, 'escape_by_ref'));
    return @vsprintf($query, $args);
}

<?php
......
/**
 * Prepares a SQL query for safe use, using sprintf() syntax
 */
function prepare($args=NULL) {
    if ( NULL === $args )
    return;
    $args = func_get_args();
    $query = array_shift($args);
    $query = str_replace("'%s'", '%s', $query); // in case someone mistakenly already singlequoted it
    $query = str_replace('"%s"', '%s', $query); // doublequote unquoting
    $query = str_replace('%s', "'%s'", $query); // quote the strings
    array_walk($args, array(&$this, 'escape_by_ref'));

    // 旧的方法会引起其他问题
    // $query = preg_replace("#(%[0-f]{2})#sie", "urldecode('$1')", $query);
    // $query = @vsprintf($query, $args);
    // $query = preg_replace("#([\x80-\xff])#se", "strtolower(urlencode('$1'))", $query);

    // 新的方法只针对重复标题时的死循环问题
    $reg = "#post_name = '((?:%[0-9a-f]{2})+.+)'#Usi";
    if (preg_match($reg, $query, $match)) {
        $he = $match[1];
        $hd = urldecode($he);
        $query = str_replace($he, $hd, $query);
        $query = @vsprintf($query, $args);
        $query = str_replace($hd, $he, $query);
    } else {
        $query = @vsprintf($query, $args);
    }

    return $query;
}