Rails, Rake aborted! undefined method 'active_record'
===

I'm sure I miss some basic thing.

I had a correctly working app in dev environment. 
Than I had some modifications that I cant correctly explain (with the migrations and tried to insert seed_dump gem).
Now every rake command drops an error:

    C:\Programozas\Rails Apps\sorsveto>rake about
    rake aborted!
    undefined method `active_record' for #<Rails::Application::Configuration:0x3e482
    98>
    
    Tasks: TOP => about => environment
    (See full trace by running task with --trace)

or

    C:\Programozas\Rails Apps\sorsveto>rake db:migrate
    rake aborted!
    Don't know how to build task 'db:migrate'
    
    (See full trace by running task with --trace)

There is my gemfile:

    source 'https://rubygems.org'
    
    gem 'rails', '3.2.2'
    gem 'bootstrap-sass', '2.0.0'
    gem 'will_paginate', '3.0.3'
    gem 'bootstrap-will_paginate', '0.0.5'
    
    group :development do
      gem 'sqlite3', '1.3.5'
      gem 'annotate', '~> 2.4.1.beta'
    end
    
    # Gems used only for assets and not required
    # in production environments by default.
    group :assets do
      gem 'sass-rails',   '~> 3.2.3'
      gem 'coffee-rails', '~> 3.2.1'
      gem 'uglifier', '>= 1.0.3'
    end
    
    gem 'jquery-rails'
    
    group :test, :development do
      gem 'rspec-rails', '~> 2.8.rc'
      gem 'shoulda', '~> 3.0.1'
      gem 'shoulda-context'
      gem 'shoulda-matchers'
      gem 'eventmachine', '1.0.0.rc.4'
      gem 'listen', '0.4.7'
      gem 'guard-livereload', '1.0.0'
      gem 'guard-rspec', '0.5.5'
      gem 'guard-spork', '0.3.2'
      gem 'spork', '0.9.0'
    end
    
    group :test do
      gem 'capybara', '1.1.2'
      gem 'factory_girl_rails', '1.4.0'
      gem 'cucumber-rails', '1.2.1'
      gem 'database_cleaner', '0.7.0'
    end
    
    # Test gems on Windows
    group :test do
      gem 'rb-fchange', '0.0.5'
      gem 'rb-notifu', '0.0.4'
      gem 'win32console', '1.3.0'
    end
    
    group :production do
      gem 'pg', '0.12.2'
    end

I can't figure out how to solve this. I tried to reinstall or install 0.8.7 and remove this (now I have version 0.9.2.2). I even tried to install 0.9.2. Many combinations (more than one at a time and run bundle exec rake XY) no success.
I even tried to insert this into my gem file:

    require 'rake/dsl_definition'
    require 'rake'

Neither helped.
Any ideas? All help mutch appriciated.
