RVM - MacPorts won't update through proxy

[admin]

I'm trying to use RVM to install ruby on my iMac.

I start by typing the following:

rvm list known

I then target the version that I want to install (the guide I'm following recommends 1.9.2 instead of the base 1.8.7) with the following line:

rvm install 1.9.2

Then I get this:

27698AM:~ butler15$ rvm install 1.9.2
Searching for binary rubies, this might take some time.
No binary rubies available for: osx/10.7/x86_64/ruby-1.9.2-p320.
Continuing with compilation. Please read 'rvm mount' to get more information on binary rubies.
Installing requirements for osx, might require sudo password.
Password:

I enter my password and I get this:

DEBUG: Copying /Users/butler15/Library/Preferences/com.apple.dt.Xcode.plist to /opt/local/var/macports/home/Library/Preferences
DEBUG: MacPorts sources location: /opt/local/var/macports/sources/rsync.macports.org/release/tarballs
--->  Updating MacPorts base sources using rsync
rsync: failed to connect to rsync.macports.org: Operation timed out (60)
rsync error: error in socket IO (code 10) at /SourceCache/rsync/rsync-42/rsync/clientserver.c(105) [receiver=2.6.9]
Command failed: /usr/bin/rsync -rtzv --delete-after rsync://rsync.macports.org/release/tarballs/base.tar /opt/local/var/macports/sources/rsync.macports.org/release/tarballs
Exit code: 10
DEBUG: Error synchronizing MacPorts sources: command execution failed
while executing
"macports::selfupdate [array get global_options] base_updated"
Error: /opt/local/bin/port: port selfupdate failed: Error synchronizing MacPorts sources: command execution failed

If I understand correctly it's trying to update MacPorts but fails due to being behind a proxy (or something?)

I've tried following this guide but it didn't work: <a href="http://samkhan13.wordpress.com/2012/06/15/make-macports-work-behind-proxy/" rel="nofollow">http://samkhan13.wordpress.com/2012/06/15/make-macports-work-behind-proxy/</a>

Further Information:

My current version of RVM and RUBY: <a href="http://d.pr/i/H1Eu" rel="nofollow">http://d.pr/i/H1Eu</a>

My OSX - 10.7.4

Thanks in advance for your help