rails3-generators does not add any generators

Question

Here is my Gemfile

gem 'rails', '3.0.0'
...
gem 'haml-rails'
gem 'jquery-rails'

group :test do
  gem 'shoulda'
  gem 'rspec'
  gem 'rspec-rails'
  gem 'factory_girl'
end

gem 'rails3-generators', :group => :development
...

I run bundle install/update. And then not all new generators (from rails3-generators) are added. haml generators are also missing:

artem:~/projects/merjis (master)$ rails g
...

Please choose a generator below.

Rails:
  controller
  generator
  helper
  integration_test
  mailer
  migration
  model
  observer
  performance_test
  plugin
  resource
  scaffold
  scaffold_controller
  session_migration
  stylesheets

ActiveRecord:
  active_record:devise

Authlogic:
  authlogic:session

Devise:
  devise
  devise:install
  devise:views

Jquery:
  jquery:install

Koala:
  koala:install

MongoMapper:
  mongo_mapper:install

Mongoid:
  mongoid:devise
  mongoid:install

Mustache:
  mustache:install

Rspec:
  rspec:install

What am I missing?

EDIT

As @shingara pointed, not all but only some generators are missing

Answer 1

I am not familiar with the rails3-generators plugin but in your config/application.rb file

config.generators do |g|
  g.template_engine :haml => this works for sure
  g.scaffold_generator :rails3-generators => if that is the generator to replace
end

you can find another example here: http://paulbarry.com/articles/2010/01/13/customizing-generators-in-rails-3

Answer 2

Factory girl, shoulda and haml do not have 'explicit' generators you can call using rails generator. You need to configure your application. Haml is automatic (through the haml-rails gem, so from now on, each time a model is generated, it will generate haml views.

For the factory-girl you have to edit config\application.rb and add

# Configure generators values
config.generators do |g|    
  g.test_framework  :rspec, :fixture => true  
  g.fixture_replacement :factory_girl, :dir=>"spec/factories"
end

and shoulda you just need to require in your spec_helper.