Toto som nasiel na webe. Ak treba preložiť, tak napíš.
Edit the file /etc/environment, for example with this command:
gksu /etc/environment
(it will ask you for your password, because you need to do it as a root)
now, add the following line to that file:
http_proxy="
http://my.proxy.address:port"
where 'my.proxy.address' and 'port' need to be replaced with the
respective values you wish to use. Save the file and relog -- make sure
the setting is there by opening a terminal and ussuing the command:
export | grep http_proxy