[Security Firewall] Proxy problems...

[Alexandre Duarte Rogoski]

It's me again!!

I have a question this time. Two proxys working (or almost) hierarchaly (I think that this must be the word). A MDK 10.1 primary server, and after a MNF 2. In the MNF we have this line in the squid.conf added manually:
cache_peer 20.20.0.1 parent 5000 3130

The clients on the first proxy can normally access the web, but the clients under MNF only access simple pages, examples:
I can access this page: http://www.bb.com.br, but this link https://www2.bancobrasil.com.br/aapf/aai/login.pbk in the page I can't and it return a 403 error. This is a bank page, and we really need access this kind of webpage, once It is a government institute with a financial sector, and another pages of banks have the same problem...

Where must be this problem?? How can I fix it??

Thanks!!