I tried all the above solutions, however none of them worked. If you're on linux/macOS i highly suggest using tsocks over an ssh tunnel. What you need in order to get this setup working is a machine where you can log in via ssh, and in addition to that a programm called tsocks installed.
The idea here is to create a dynamic tunnel via SSH (a socks5 proxy). We then configure tsocks to use this tunnel and to start our applications, in this case:
tsocks gem install ...
or to account for rails 3.0:
tsocks bundle install
A more detailed guide can be found under:
http://blog.byscripts.info/2011/04/bypass-a-proxy-with-ssh-tunnel-and-tsocks-under-ubuntu/
Despite being written for Ubuntu the procedure should be applicable for all Unix based machines. An alternative to tsocks for Windows is FreeCap (http://www.freecap.ru/eng/). A viable SSH client on windows is called putty.
answered 2011-09-06T05:04:51.830