[squid-users] forwarded to the same URL each time

Hello,

I have just installed a squid proxy on... let's call the machine "fooproxy",
which is supposed to be a secondary cache (I have no idea of the parent
cache's nature and configuration, except its name and that browsers access
it via port 80).
I configured it in order to save bandwith on my local subnetwork & reduce
the (taxed) calls to this proxy.
I join my squid.conf as attached file to give you an idea.
My problem is that whatever url I type in browsers using "fooproxy" as
proxy, I am forwarded to the "fooproxy" 's Apache server's default page.
I declared a remote proxy in my Apache's configuration file as written in
the FAQ but there is obviously something I didn't catch.
May you give me a way to look at?

Thanks in advance,
Grégory