CMemCache file not found

I just try implementing cmemcache into my application. when i run the application, i receive an error saying:

PHP Error[2]: include(Memcache.php): failed to open stream: No such file or directory in file /var/www/html/yii-1.1/framework/YiiBase.php at line 338

is it an spelling error at yii framework or i have any mistake made on my side?

thanks in advance.

Memcache extension is missing I guess. Check phpinfo().

// Or how did you define it in config? Cache ‘class’ must be ‘CMemCache’

sorry it’s my mistake. i did’t install the extension properly.