4
aahhhh yes, I'm happy to find an answer following my discover.
With the Gzip encoding there is no secret, to be completely sure that it's working, you should and you must check apache log files, and see the content size of the sent page with and without gzip. You will see a great loss of size or not. It's the only real, secure way to verify the Gzip.
A lot of people are thinking to use gzip on their website, but in fact, it's really easy to be wrong. It's not only a simple call to a gz_handler() function which will make it ...
please take a look at jpcache
http://www.jpcache.com/ which is the best gzip encoding / cache algorithm available for PHP. If you use this on a website, you can be sure to have on-the-fly gziped website.
And in term of performance, I think XOOPS need a good Gzip, because it's not "really" fast ... (but I still like a lot XOOPS which the best CMS I ever used !
)