Error: Undefined function call Stripos()

I am trying to use Google CSE Search with my Drupal site and getting a strange error... at the moment I activate the CSE block in my page I begin getting this error:

Call to undefined function: stripos() in F:\webspace\disk15\Newfreak\www\sites\all\modules\adsense\adsense.module on line 542

For every page in my site. Nothing helps except for deleting the Adsense directory from the modules folder.

Hoping for any idea that can help from here....

TIA,

Helio