Autotest stalls when launched

Question

I'm trying to get a Rails (version 2.3.5) app set up to run RSpec and Autotest.

I've got both rspec (1.2.9) and rspec-rails (1.2.9) vendored as plugins in the app. I then have ZenTest 4.4.0, Autotest (4.3.2) and Autotest Rails (4.1.0) gems installed.

Whenever I run the autotest command in the app, all I get is this:

loading autotest/rails
style: Rails

And then it just sits there and never actually runs any of the test.