use new pdo drriver for SQLIte

[eluser]Unknown[/eluser]
hi
i noticed in new version of CI (2.1.0) there is a PDO driver, but i could noy use it for connecting to SQLite database.
i used this code in config/database.php

Code:

$db['default']['dbdriver'] = 'pdo';
$db['default']['database'] = 'sqlite:db/db.sqlite';

but i got error messages, does anyone here tried to use new pdo driver for connecting to sqlite, if so, plz share the approach here.
tanX