porting i18n library to 2.0 - CI_Controller not found

[eluser]froginvasion[/eluser]
On the IRC channel, somebody gave me the hint that it might be a version error, but well.. I don't know. It concerns the following library:

http://codeigniter.com/wiki/CodeIgniter_...tion_i18n/

With some minor bugfixing, the code does what's expected and prescribed. But this is not exactly what I want to have. I was trying to modify the code so it does what I want.
For that I tried getting an instance of $CI in function MY_lang(), just after the construct.

Code:

function MY_Lang()
    {
        parent::__construct();
        
        global $CFG;
        global $URI;
        global $RTR;
        
        $CI =& get_instance();

this gives the following error:

Fatal error: Class 'CI_Controller' not found in /**myproject**/system/core/CodeIgniter.php on line 210

Anyone got an idea what I'm doing wrong?
If you look in the code of the extension, you can see
that a CI instance is being retrieved in another function,
and that never fails. However... that function is never used.