This is a bad idea.
apt-get install something ... error - corrupt data.
Don't do. It's worse than hijacking the sessions into a proxy in the first place.
With the plethora of spyware around on the average PC, hijacking port 80 connections is a great way to monitor and block them. You can configure legitimate programs to use a proxy (apt for example or even ftp for apt), and illegitimate ones fail silently. For spyware, thats a good thing.
Robert, we don't all live in a squid-erific world, fact is, hijacking connections is a great way to save bandwidth, monitor useage and filter sites. I love squid, and you do great work, but sometimes I feel like you haven't seen the shit some people suck off the net :)
dave -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
