UTF-8 to Unicode Code Points

Is there a function that will change UTF-8 to Unicode leaving non special characters as normal letters and numbers?

ie the German word "tchüß" would be rendered as something like "tch\20AC\21AC" (please note that I am making the Unicode codes up).

EDIT: I am experimenting with the following function, but although this one works well with ASCII 32-127, it seems to fail for double byte chars:

function strToHex ($string){    $hex = '';    for ($i = 0; $i < mb_strlen ($string, "utf-8"); $i++)    {        $id = ord (mb_substr ($string, $i, 1, "utf-8"));        $hex .= ($id <= 128) ? mb_substr ($string, $i, 1, "utf-8") : "&#" . $id . ";";}    return ($hex);}

Any ideas?

EDIT 2: Found solution: The PHP ord() function does not work for double byte chars. Use instead: http://nl.php.net/manual/en/function.ord.php#78032