Native Autoload - by Phil Sturgeon.

gistfile1.txt

/*
| -------------------------------------------------------------------
|  Native Autoload - by Phil Sturgeon. New Version!
| -------------------------------------------------------------------
|
| Nothing to do with config/autoload.php, this allows PHP autoload to work
| for base controllers and some third-party libraries.
|
| If using HMVC you do not need this! HMVC will autoload.
|
| Place this code at the bottom of your application/config/config.php file.
*/
function __autoload($class)
{
    if (strpos($class, 'CI_') !== 0)
    {
        if (file_exists($file = APPPATH . 'core/' . $class . EXT))
        {
            include $file;
        }

        elseif (file_exists($file = APPPATH . 'libraries/' . $class . EXT))
        {
            include $file;
        }
    }
}