I've configured external ACL's:

external_acl_type wbinfo_group ttl=3D0 concurrency=3D5 %LOGIN /usr/local/=
squid/libexec/wbinfo_group.pl

acl usuarios proxy_auth REQUIRED
acl internetfull external wbinfo_group -i "/usr/local/squid/etc/internetf=
ull"
acl internetayp external wbinfo_group -i "/usr/local/squid/etc/internetay=
p"
acl dominiosayp dstdomain www.macromedia.com

http_access allow usuarios internetfull
http_access deny usuarios internetayp !dominiosayp
http_access deny all

Some reports talk about bugs in wbinfo_group.pl

I'm using squid 2.5.5 and samba 3.0.2a

The authentication is OK, but in access.log writes these entries:

1081796269.868 1888 172.16.62.4 TCP_DENIED/403 1438 GET http://www.faqs=
..org/docs/howtos1.html
CASDOM01/LUISC NONE/- text/html

while the user CASDOM01/LUISC belongs to "internetfull" group

Thanks.