Cache Problem

[eluser]Unknown[/eluser]
I solved my problem editing the method cache in codeigniter/libraries/output.php.

Code:

function cache($time)
{
  $CI =& get_instance();    
  $enable_cache = $CI->config->item('enable_cache');
  $this->cache_expiration = (
    (is_numeric($time) && $enable_cache) ?
    $time :
    0        
  );
}

I have no idea if this is the best place but at least it made some sence.
Tiago