Cwebmodule Can Not Be Found

My project separates the code into backend, common, console, and frontend folders, and I have installed the module in a subfolder of the backend folder. When I try and access the module, I get an error that CWebModule can not be found.

I am not sure what I need to do to insure that following php code - class ImportcsvModule extends CWebModule will work.

Please note the the yii framework CwebModule class is located in the folder - \common\lib\Yii\web\CWebModule.

Any help would be greatly appreciated