title: Gem's aren't working in production
body: <p>I'm using some gem in my application, but I'm some problems whith this.</p>
  
  <p>In a form, I'm using gem cocoon for create nested fields, I'm using datatable for sorting columns too.</p>
  
  <p>But these gem aren't not working in production.</p>
  
  <p>I put the gem out assets group, I tried use: rake assets:precompile --trace before to execute the application, but still don't working.</p>
  
  <p>My gemfile:</p>
  
  <pre><code>source 'https://rubygems.org'
  
  gem 'rails', '~&gt; 3.2.16'
  gem 'mysql2', '~&gt; 0.3.14'
  
  # Autenticação
  gem 'authlogic', '~&gt; 3.3.0'
  
  # Autorização
  gem 'cancan'
  
  # Anexos
  gem 'paperclip', '~&gt; 3.0'
  
  # Mailer
  gem 'mail', '~&gt; 2.5.4'
  
  # Custom select 
  gem "bootstrap-select-rails", "~&gt; 1.3.0"
  
  # 
  gem 'whenever', :require =&gt; false
  
  # Nested fields
  gem 'cocoon'
  
  # Bundle edge Rails instead:
  # gem 'rails', :git =&gt; 'git://github.com/rails/rails.git'
  
  # Gems used only for assets and not required
  # in production environments by default.
  group :assets do
  
    gem 'sass-rails',   '~&gt; 3.2.3'
    gem 'coffee-rails', '~&gt; 3.2.1'
  
    # See https://github.com/sstephenson/execjs#readme for more supported runtimes
    # gem 'therubyracer', :platforms =&gt; :ruby
  
    gem 'uglifier', '~&gt; 1.0.3'
  
  end
  gem 'therubyracer', '~&gt; 0.12.0'
  
  gem 'jquery-datatables-rails', github: 'rweng/jquery-datatables-rails'
  
  gem 'less-rails'
  gem 'jquery-rails'
  gem 'jquery-ui-rails', '~&gt; 4.1.1'
  
  # twitter bootstrap css &amp; javascript toolkit
  gem 'twitter-bootswatch-rails', '~&gt; 3.0.3'
  
  # twitter bootstrap helpers gem, e.g., alerts etc...
  gem 'twitter-bootswatch-rails-helpers'
  </code></pre>
  
  <p>config/production.rb</p>
  
  <p>Curriculum::Application.configure do
        # Settings specified here will take precedence over those in config/application.rb</p>
  
  <pre><code>  # Code is not reloaded between requests
    config.cache_classes = true
  
    # Full error reports are disabled and caching is turned on
    config.consider_all_requests_local       = false
    config.action_controller.perform_caching = true
  
    # Disable Rails's static asset server (Apache or nginx will already do this)
    config.serve_static_assets = false
  
    # Compress JavaScripts and CSS
    config.assets.compress = true
  
    # Don't fallback to assets pipeline if a precompiled asset is missed
    config.assets.compile = false
  
    # Generate digests for assets URLs
    config.assets.digest = true
  
    # Compress JavaScripts and CSS
    config.assets.compile = true
  
    #config.assets.precompile += %w( *.js *.css )
    #config.serve_static_assets = true
    config.assets.initialize_on_precompile = false
  
    config.i18n.fallbacks = true
  
    # Send deprecation notices to registered listeners
    config.active_support.deprecation = :notify
  
   end
  </code></pre>
  
  <p>application.js</p>
  
  <pre><code> //= require jquery
   //= require jquery_ujs
   //= require bootstrap
   //= require jquery.ui.all
   //= require jquery.ui.tabs
   //= require jquery.ui.tabs.min
   //= require bootstrap-tabs
   //= require interns
   //= require systems_analysts
   //= require generics
   //= require file_field
   //= require bootstrap-filestyle
   //= require dataTables/jquery.dataTables
   //= require dataTables/jquery.dataTables.bootstrap
   //= require cocoon
  </code></pre>
  
  <p>Log</p>
  
  <pre><code> =&gt; Rails 3.2.16 application starting in production on http://0.0.0.0:3000
   =&gt; Call with -d to detach
   =&gt; Ctrl-C to shutdown server
   [deprecated] I18n.enforce_available_locales will default to true in the future. If you      really want to skip validation of your locale you can set I18n.enforce_available_locales = false to avoid this message.
   [2014-02-04 11:08:45] INFO  WEBrick 1.3.1
   [2014-02-04 11:08:45] INFO  ruby 1.9.3 (2013-06-27) [x86_64-linux]
   [2014-02-04 11:08:45] INFO  WEBrick::HTTPServer#start: pid=2567 port=3000
   Started GET "/hr_curriculum_generics/new" for 127.0.0.1 at 2014-02-04 11:08:45 -0200
   Processing by HrCurriculumGenericsController#new as HTML
     Rendered shared/_error_messages.html.erb (0.7ms)
     Rendered hr_curriculum_generics/_generic_company_fields.html.erb (2.0ms)
     Rendered hr_curriculum_generics/_form.html.erb (144.0ms)
     Rendered hr_curriculum_generics/new.html.erb within layouts/application (151.7ms)
   Completed 200 OK in 382.1ms (Views: 286.4ms | ActiveRecord: 4.6ms)
   [2014-02-04 11:08:46] WARN  Could not determine content-length of response body. Set content-length of the response or set Response#chunked = true
   Started GET "/assets/cerulean-e95335988bef420c8d08256a4348651d.css" for 127.0.0.1 at 2014-02-04 11:08:46 -0200
   Served asset /cerulean-e95335988bef420c8d08256a4348651d.css - 304 Not Modified (0ms)
   [2014-02-04 11:08:46] WARN  Could not determine content-length of response body. Set content-     length of the response or set Response#chunked = true
   Started GET "/assets/application-112486149e37a46f8edf68319a3cc0da.js" for 127.0.0.1 at 2014-02-04 11:08:46 -0200
   Served asset /application-112486149e37a46f8edf68319a3cc0da.js - 304 Not Modified (107ms)
   Started GET "/assets/logo-scaled-3757028be58a8cc4ac22912194a7f4e3.png" for 127.0.0.1 at 2014-02-04 11:08:46 -0200
   Served asset /logo-scaled-3757028be58a8cc4ac22912194a7f4e3.png - 304 Not Modified (0ms)
   [2014-02-04 11:08:46] WARN  Could not determine content-length of response body. Set content-length of the response or set Response#chunked = true
   [2014-02-04 11:08:46] WARN  Could not determine content-length of response body. Set      content-length of the response or set Response#chunked = true
  </code></pre>