[Zope] Zope, Squid and Apache

Looking at the various bits of documentation for setting up Squid as an httpd accelerator for Zope leaves me a bit confused, especially on how to reconfigure Apache. It looks as though Squid should run as a listener on port 80, but how do I set it up as an accelerator for both Zope and Apache? And do I no longer need to set up any Rewrite rules in Apache? I'm having a difficult time picturing how the whole thing hangs together... -- John