title: image-url doesnt add a generated string to image assets in production. Rails 3.1 and Compass
body: <p>In my sass files I use image-url('image.png') to add my images but in production they arent working. It should add a string to my images but it isnt doing it. Somebody has a clue how I can fix this?</p>
  
  <p>I use compass version 0.12.alpha.0
  And rails version 3.1.0</p>
  
  <p>Bundle </p>
  
  <pre><code>Using rake (0.9.2) 
  Using multi_json (1.0.3) 
  Using activesupport (3.1.0) 
  Using bcrypt-ruby (3.0.1) 
  Using builder (3.0.0) 
  Using i18n (0.6.0) 
  Using activemodel (3.1.0) 
  Using erubis (2.7.0) 
  Using rack (1.3.4) 
  Using rack-cache (1.0.3) 
  Using rack-mount (0.8.3) 
  Using rack-test (0.6.1) 
  Using hike (1.2.1) 
  Using tilt (1.3.3) 
  Using sprockets (2.0.2) 
  Using actionpack (3.1.0) 
  Using mime-types (1.16) 
  Using polyglot (0.3.2) 
  Using treetop (1.4.10) 
  Using mail (2.3.0) 
  Using actionmailer (3.1.0) 
  Using arel (2.2.1) 
  Using tzinfo (0.3.29) 
  Using activerecord (3.1.0) 
  Using activeresource (3.1.0) 
  Using airbrake (3.0.4) 
  Using ansi (1.3.0) 
  Using archive-tar-minitar (0.5.2) 
  Using bundler (1.0.18) 
  Using highline (1.6.2) 
  Using net-ssh (2.2.1) 
  Using net-scp (1.0.4) 
  Using net-sftp (2.0.5) 
  Using net-ssh-gateway (1.1.0) 
  Using capistrano (2.9.0) 
  Using chunky_png (1.2.5) 
  Using coffee-script-source (1.1.2) 
  Using execjs (1.2.9) 
  Using coffee-script (2.2.0) 
  Using columnize (0.3.4) 
  Using fssm (0.2.7) 
  Using sass (3.1.10) 
  Using compass (0.12.alpha.0) 
  Using compass-960-plugin (0.10.4) 
  Using rest-client (1.6.7) 
  Using couchrest (1.1.2) 
  Using couchrest_model (1.1.2) 
  Using daemons (1.0.10) 
  Using diff-lcs (1.1.3) 
  Using factory_girl (2.0.2) 
  Using rack-ssl (1.3.2) 
  Using json (1.6.1) 
  Using rdoc (3.10) 
  Using thor (0.14.6) 
  Using railties (3.1.0) 
  Using factory_girl_rails (1.1.0) 
  Using rails (3.1.0) 
  Using formtastic (2.0.0.rc5) 
  Using gem_plugin (0.2.3) 
  Using geokit (1.6.0) 
  Using gravatar (1.0) 
  Using haml (3.1.3) 
  Using haml-rails (0.3.4) 
  Using jquery-rails (1.0.14) 
  Using libv8 (3.3.10.2) 
  Using ruby_core_source (0.1.5) 
  Using linecache19 (0.5.12) 
  Using metaclass (0.0.1) 
  Using mocha (0.10.0) 
  Using money (3.1.5) 
  Using mongrel (1.2.0.pre2) 
  Using nifty-generators (0.4.6) 
  Using rspec-core (2.6.4) 
  Using rspec-expectations (2.6.0) 
  Using rspec-mocks (2.6.0) 
  Using rspec (2.6.0) 
  Using rspec-rails (2.6.1) 
  Using ruby-debug-base19 (0.11.25) 
  Using ruby-debug19 (0.11.6) 
  Using sass-rails (3.1.4) 
  Using state_machine (1.0.2) 
  Using therubyracer (0.9.4) 
  Using turn (0.8.2) 
  Using uglifier (1.0.3)
  </code></pre>
  
  <p>production.rb</p>
  
  <pre><code>MyApp::Application.configure do
  
    config.cache_classes = true
    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
  
    # Specify the default JavaScript compressor
    config.assets.js_compressor  = :uglifier
  
    # Specifies the header that your server uses for sending files
    # (comment out if your front-end server doesn't support this)
    config.action_dispatch.x_sendfile_header = "X-Sendfile" # Use 'X-Accel-Redirect' for nginx
  
    config.generators.stylesheet_engine = :sass
  end
  </code></pre>