Acts_as_ratable method not found

After i install the acts_as_ratable plugin, my app says

[code=]NameError in UploadController#list

undefined local variable or method `acts_as_rateable’ for Jclass:Class
RAILS_ROOT: script/…/config/…

Application Trace | Framework Trace | Full Trace
method_missing' app/models/jclass.rb:2 app/controllers/upload_controller.rb:12:inlist’[/code]
I’ve tried installing the plugin from 2 diffrent places, neither seem to
fix the issue. Here my model code

[code=]class Jclass < ActiveRecord::Base
file_column :file
belongs_to :user
acts_as_ferret :fields => [:author, :title, :description]
acts_as_textiled :description
validates_presence_of :title, :description, :file
validates_uniqueness_of :title
has_many :jcomments
validates_format_of :file,
:with => %r{.(java|jar|zip)$}i,
:message => “must be a .java, .jar or .zip file”

and heres the list method in the upload controller:

def list @jclass_pages, @jclasses = paginate :jclasses, :per_page => 10 end