trouble creating a gem

gem_trouble

My directory structure is this:

| - rest-in-motion.gemspec
| - /lib
     | - rest-in-motion.rb
     | - /rest-in-motion
         |
         | - 5 .rb files that make up the gem

The contents of rest-in-motion.gemspec are:

Gem::Specification.new do |s|
  s.name        = 'rest-in-motion'
  s.version     = '0.0.4'
  s.date        = '2012-06-23'
  s.summary     = 'Object mapping.'
  s.description = 'Object mapping layer atop RestKit\'s RKClient.'
  s.authors     = ['Nick Pachulski']
  s.email       = '[email protected]'
  s.files       = ['lib/rest-in-motion']
  s.homepage    = 'http://nickpachulski.com/'
end

and the contents of rest-in-motion.rb are:

unless defined?(Motion::Project::Config)
  raise "This file must be required within a RubyMotion project Rakefile."
end

Motion::Project::App.setup do |app|
  Dir.glob(File.join(File.dirname(__FILE__), 'rest-in-motion/*.rb')).each do |file|
    app.files.unshift(file)
  end
end

And I build with: 

gem build rest-in-motion.gemspec

Which builds successfully all fine and good, and I can then do a:

gem install ./rest-in-motion-0.0.4.gem

But I can never do a require in IRB or PRY without getting:

1.9.3 (main):0 > require 'rest-in-motion'
LoadError: cannot load such file -- rest-in-motion
from /Users/pachun/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'