Installing autotest with Rails 3.1 and RSpec on Ubuntu 10.10

My environment:
RVM 1.6.14
Ubuntu 10.10
Ruby 1.9.2
Rails 3.1.rc1
RSpec 2.6.4

First install the autotest gem (currently version 4.4.6). Since I'm in a project gemset (through RVM), I don't need "sudo":

$ gem install autotest

Next install the Rails helper gem for autotest (currently version 4.1.2):

$ gem install autotest-rails-pure

Then install the libnotify-bin package (currently version 0.5.0):

$ sudo apt-get install libnotify-bin

Then install the autotest-notification gem (currently version 2.3.1)

$ gem install autotest-notification

This gives you the executable "an-install", which you should to run:

$ an-install

Now start the regular autotest gem:

$ autotest

That's it. Now you should get automatic desktop notification of passing and failing tests each time you change a file covered by a test. For complete instructions, see the README at Carlos Brando's autotest-notification gem.