title: Simple Compass CSS Error
body: <p>I am learning Compass with Django/Zinnia. Running the following to produce css produces an error that I don't really understand. Thanks!</p>
  
  <pre><code>cd /var/www/static/zinnia
  
  compass compile ./ --trace
  LoadError on line ["36"] of /usr/lib/ruby/1.9.1/rubygems/custom_require.rb: cannot load such file -- susy
  /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/data.rb:161:in `require'
  /var/www/static/zinnia/./config.rb:2:in `get_binding'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/serialization.rb:24:in `eval'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/serialization.rb:24:in `parse_string'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/serialization.rb:15:in `block in _parse'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/serialization.rb:14:in `open'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/serialization.rb:14:in `_parse'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/file_data.rb:7:in `block in new_from_file'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/inheritance.rb:204:in `with_defaults'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/file_data.rb:6:in `new_from_file'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/helpers.rb:42:in `configuration_for'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/configuration/helpers.rb:97:in `add_project_configuration'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/commands/project_base.rb:31:in `add_project_configuration'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/commands/project_base.rb:25:in `configure!'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/commands/project_base.rb:15:in `initialize'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/commands/update_project.rb:37:in `initialize'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/exec/sub_command_ui.rb:42:in `new'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/exec/sub_command_ui.rb:42:in `perform!'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/lib/compass/exec/sub_command_ui.rb:15:in `run!'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/bin/compass:30:in `block in &lt;top (required)&gt;'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/bin/compass:44:in `call'
  /var/lib/gems/1.9.1/gems/compass-0.12.2/bin/compass:44:in `&lt;top (required)&gt;'
  /usr/local/bin/compass:23:in `load'
  /usr/local/bin/compass:23:in `&lt;main&gt;'
  </code></pre>