If you happen to run a squid inside a Linux-Vserver you should make sure that you’ve set tcp_outgoing_address to the primary IP of the vserver or you’ll encounter strange issues resulting in https not working from within the vserver:
1310903352.277 0 1.2.3.4 TCP_MISS/500 0 CONNECT bugzilla.redhat.com:443 user NONE/- -

Thank you SO much! I had already given up hope…