Useful function for getting a random key
private function _getRandomKey($md5=false){   
    $char = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';    
    $key = '';    
    $char_length = strlen($char)-1; 
    for ($i = 0; $i != 32;  $i++){   
        $random_pos = rand(0, $char_length);    
        $key .= $char{$random_pos};    
    } 
    return $key = $md5 ? md5($key) : $key;   
}
 
 


