spork: DRb::DRbConnError any time RSpec tries to use Spork

Any time I run Spork and attempt to connect to it via rspec --drb, RSpec exits with an exception and Spork throws a DRb::DRbConnError. I am pretty much at a loss as to what could be going on here. Any ideas?

Running tests with args ["--color", "spec/views/servers/access_tokens.xml.builder_spec.rb"]...
Exception encountered: #<DRb::DRbConnError: druby://localhost:51542 - #<Errno::ECONNREFUSED: Connection refused - connect(2)>>

Full output from both Spork and RSpec commands here: https://gist.github.com/318c12c94b8d7740a3ba