problem with s3upload extension, need help

Hi all,

i want to upload file to s3 and i already have all the information. I follow the official website step. Add s3upload to config/main.php and fill in all the infomration but return error msg like below:

Property "CWebApplication.s3" is not defined.

can anyone tell me what is the error that i did?

‘components’=>array(

    's3upload' => array(


    'class'=>'ext.s3upload.CS3Upload',


    'aKey' => <AWS Access key>,


    'sKey' => <AWS Secret key>,


    'bucket' => <Default Bucket>,


),

<?php echo Yii::app()->s3upload->Form($bucket, $uri, $redirect, $maxFileSize); ?>