yii and mongo Db

i have just begun using mongo db with yii and i started with a basic TO-Do List application

i have extracted the yii mongo db suite in the extension folder of my application but when i run my application i get the following error:

include(EMongoCriteria.php) [<a href=‘function.include’>function.include</a>]: failed to open stream: No such file or directory

Kindly reply

Thank You