[squid-users] ACL Woes

Hello,

I'm currently looking to implement a rule that allows people behind
the proxy to access a specific URL. In my case the URL is
https://mail.google.com/a/domain.tld.

We are using GApps, but I don't want them to be able to use
mail.google.com to access typical gmail.

I used:

acl Google url_regex -i ^https://mail.google.com/a/domain.tld$
http_access allow Google

Does it simply not work this way?

-- 
Aaron Drever