If your Be machine is connected to the net via a proxy server or behind a firewall, you’ll find you can’t do anything online from the Terminal, since Terminal doesn’t understand proxy settings. However, there is a workaround for FTP — you just have to type in the commands a little differently. To get to ftp.be.com for instance, do this:
ftp your.firewall.ip.address (this connects to your firewall)
anonymous@ftp.be.com (this line tells the firewall to FTP elsewhere)
username@email.address (regular address you give as password for anon. FTP)
That should get you in with most proxy servers, but not all of them. Notably, it will probably work with Apache in proxy mode, but won’t work with, for example, SOCKS. Other popular proxies, such as WinGate, have their own syntax for handling similar situations — consult your proxie’s documentation for details.