We're having problems accessing Korean Government sites like parcel.epost.go.kr and www.g2b.go.kr<http://www.g2b.go.kr> from a squid cache that is physically in Seoul, Korea. I performed network captures and found that if the request included a 'Cache-Control' header the remote server did not send TCP ACK messages back for the request. The remote server did complete the three-way TCP connection handshake, but would not acknowledge the request. When I stripped the 'Cache-Control' header using acl NoCacheCtl dstdomain .epost.go.kr .gtb.go.kr header_access Cache-Control deny NoCacheCtl the TCP ACKs started coming back and we could retrieve content. My guess is there is a firewall protecting the remote web servers. Has anyone seen this behavior before? Mike Mitchell SAS Institute Inc. Mike.Mitchell@xxxxxxx (919) 531-6793