iTunes and Proxies

Dear all,
Kindly note that i’m working on Apple G4 iBook using OS 10.4.8 and
facing a problem connecting my iTunes (7.02) to the store under my
company network. It gives a message telling that i have to access the
proxies first and all proxies configuration are well inserted. Is there any
one who can help to know witch files shall i enable from the firewall in
order to be able to access the store without mentioning proxies
problems. I’m having McAffee as firewall.
Regards.