Apache monitoring tool

Hi, I am using this monitoring tool to monitor my apache requests and workers, but I can make it work, no data in graphs.
This is my cacti log:
09/24/2012 04:45:05 PM - CMDPHP: Poller[0] Host[4] DS[52] CMD: /usr/local/bin/php -q /var/www/cacti/scripts/ss_get_by_ssh.php --host www.myhost.com --type apache --items g0, output: g0:-1

Now, if I execute the same line with root in my console I have a good result:
/usr/local/bin/php -q /var/www/cacti/scripts/ss_get_by_ssh.php --host www.myhost.com --type apache --items g0
g0:4897174

So, I think its a permission issue but I dont know why.
Any help will be great.

Thanks

If relevant anymore you can run the same command as ‘cacti’ user and see the result:
sudo -u cacti …