title: Bundle doesn't want to install a gem (not yet checked out)
body: <p>I want to run a Ruby on rails server, but a certain gem doesn't want to install. This rails program is not compatible with ruby 2.0, so I want to use ruby 1.9.3, which I installed, but I can't bundle install anymore...</p>
  
  <pre><code>$ bundle install
  # ...
  Your bundle is complete!
  Use `bundle show [gemname]` to see where a bundled gem is installed.
  $ bundle exec rails s
  git://github.com/goodtouch/jbuilder.git (at master) is not yet checked out. Run `bundle install` first.
  $ bundle show jbuilder
  /Users/julien/.bundler/ruby/2.0.0/jbuilder-7fb0eae924c7
  $ ruby --version
  ruby 1.9.3p545 (2014-02-24 revision 45159) [x86_64-darwin13.1.0]
  </code></pre>
  
  <p>In the <code>Gemfile</code>, I specified <code>ruby "1.9.3"</code>, then I ran <code>bundle install</code> again and got:</p>
  
  <pre><code>Your Ruby version is 2.0.0, but your Gemfile specified 1.9.3
  </code></pre>
  
  <p>The <code>Gemfile</code> line for this specific gem:</p>
  
  <pre><code>gem 'jbuilder', git: "git://github.com/goodtouch/jbuilder.git"
  </code></pre>
  
  <p>And what I get in the <code>Gemfile.lock</code>:</p>
  
  <pre><code>GIT
    remote: git://github.com/goodtouch/jbuilder.git
    revision: 7fb0eae924c77318ede344f32a5c208b91cdbaac
    specs:
      jbuilder (0.4.1)
        activesupport (&gt;= 3.0.0)
        blankslate (&gt;= 2.1.2.4)
  </code></pre>
  
  <p>I really don't understand what's going on. I'm under Mac OS X.</p>
  
  <p>Thank you.</p>