3
It is because you don't have any PHPSESSID in your URLs

Check your phpinfo() and normally you should have this parameter session.use_trans_sid off
My host doesn't give me the choice and this parameter is ON.
So when someone, which doesnt accept cookies, surf on my site he has PHPSESSID in URL

And that's bad for sipder.
I tried to look at common.php and I have no idea how I can disable it :/
Is Session used for anonymous (visitor not logged) ?
Thanks in advance