WordPress: Redirect CF7

No functions.php:

function ip_wpcf7_mail_sent($wpcf7)
{
    $on_sent_ok = $wpcf7->additional_setting('ip_on_sent_ok', false);

    if (is_array($on_sent_ok) && count($on_sent_ok) > 0)
    {
        wp_redirect(trim($on_sent_ok[0]));
        exit;
    }
}

Nas configurações adcionais do Form:

ip_on_sent_ok: http://example.com