>> From the squid server with an ftp client I can connect > > with those sites without trouble.
You can connect to the ftp sites from the squid server,but not from the client side. Check this. squid faq 12.17 Can I make my regular FTP clients use a Squid cache? Nope, its not possible. Squid only accepts HTTP requests. It speaks FTP on the server-side, but not on the client-side. The very cool wget will download FTP URLs via Squid (and probably any other proxy cache). Regards, Muthukumar.