Fix for issue #522

lib/compass/configuration/helpers.rb

@@ -78,6 +78,7 @@ module Compass
       end
 
       def configure_rails!(app)
+        return unless app.config.respond_to?(:sass)
         app.config.compass.to_sass_engine_options.each do |key, value|
           app.config.sass.send(:"#{key}=", value)
         end