Rails 4.0 - method_missing: with_options issue with models - ruby-on-rails

Question

I have an issue with rails 4 application. In my User model (actually, it's the same with any other model) I can't use with_options method. If I have a code like this:
class User < ActiveRecord::Base
# ...
with_options :unless => :is_person do |u|
u.validates :company_name, presence: true
u.validates :company_address, presence: true
end
# ...
end
I end up with a message like this, at the boot time of my application:
> Booting WEBrick
=> Rails 4.0.0 application starting in development on http://0.0.0.0:3000
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
Exiting
/Users/mike/.rvm/gems/ruby-2.0.0-p0#leo4/gems/activerecord-4.0.0/lib/active_record/dynamic_matchers.rb:22:in `method_missing': undefined method `  with_options' for #<Class:0x007fed97c0a6e8> (NoMethodError)
from /Users/mike/dev/leo4/app/models/user.rb:57:in `<class:User>'
...
The picture is the same, if this block is empty with no validations at all.
Something really weird is going on, because the method exists if I just remove these lines, fire up a console and check for it. It looks like its a boot time only problem (?)
Any thoughts? Thanks!
P.S. My Gemfile.lock:
GIT
remote: git://github.com/gregbell/active_admin.git
revision: 72a9c30cef47b3f38c38039de021aaa3194c188b
branch: rails4
specs:
activeadmin (0.6.0)
arbre (>= 1.0.1)
bourbon (>= 1.0.0)
coffee-rails (>= 3.2.0)
devise (>= 3.0.2)
formtastic (>= 2.3.0.rc2)
inherited_resources (>= 1.4.1)
jquery-rails (>= 3.0.0)
jquery-ui-rails (>= 4.0.0)
kaminari (>= 0.13.0)
rails (>= 3.2.0)
ransack (>= 1.0.0)
sass-rails (>= 3.2.0)
GIT
remote: git://github.com/justinfrench/formtastic.git
revision: cd6cb88f28ea7444267802ced8e5ec0f5cfd0f90
branch: master
specs:
formtastic (2.3.0.rc2)
actionpack (>= 3.0)
GIT
remote: git://github.com/sporkrb/spork-rails.git
revision: 3224f84d8c31fcb0894e9a43f6c3ac67e3aa0d71
specs:
spork-rails (3.2.1)
rails (>= 3.0.0, < 5)
spork (>= 1.0rc0)
GEM
remote: https://rubygems.org/
specs:
actionmailer (4.0.0)
actionpack (= 4.0.0)
mail (~> 2.5.3)
actionpack (4.0.0)
activesupport (= 4.0.0)
builder (~> 3.1.0)
erubis (~> 2.7.0)
rack (~> 1.5.2)
rack-test (~> 0.6.2)
activemodel (4.0.0)
activesupport (= 4.0.0)
builder (~> 3.1.0)
activerecord (4.0.0)
activemodel (= 4.0.0)
activerecord-deprecated_finders (~> 1.0.2)
activesupport (= 4.0.0)
arel (~> 4.0.0)
activerecord-deprecated_finders (1.0.3)
activesupport (4.0.0)
i18n (~> 0.6, >= 0.6.4)
minitest (~> 4.2)
multi_json (~> 1.3)
thread_safe (~> 0.1)
tzinfo (~> 0.3.37)
annotate (2.5.0)
rake
arbre (1.0.1)
activesupport (>= 3.0.0)
arel (4.0.0)
atomic (1.1.13)
bcrypt-ruby (3.1.1)
bourbon (3.1.8)
sass (>= 3.2.0)
thor
builder (3.1.4)
cancan (1.6.10)
capybara (2.1.0)
mime-types (>= 1.16)
nokogiri (>= 1.3.3)
rack (>= 1.0.0)
rack-test (>= 0.5.4)
xpath (~> 2.0)
capybara-webkit (1.0.0)
capybara (~> 2.0, >= 2.0.2)
json
coffee-rails (4.0.0)
coffee-script (>= 2.2.0)
railties (>= 4.0.0.beta, < 5.0)
coffee-script (2.2.0)
coffee-script-source
execjs
coffee-script-source (1.6.3)
cucumber (1.3.7)
builder (>= 2.1.2)
diff-lcs (>= 1.1.3)
gherkin (~> 2.12.1)
multi_json (~> 1.7.5)
multi_test (>= 0.0.2)
database_cleaner (1.0.1)
devise (3.0.2)
bcrypt-ruby (~> 3.0)
orm_adapter (~> 0.1)
railties (>= 3.2.6, < 5)
warden (~> 1.2.3)
diff-lcs (1.2.4)
draper (1.2.1)
actionpack (>= 3.0)
activesupport (>= 3.0)
request_store (~> 1.0.3)
erubis (2.7.0)
execjs (1.4.0)
multi_json (~> 1.0)
factory_girl (4.2.0)
activesupport (>= 3.0.0)
factory_girl_rails (4.2.1)
factory_girl (~> 4.2.0)
railties (>= 3.0.0)
faraday (0.8.8)
multipart-post (~> 1.2.0)
ffaker (1.18.0)
gherkin (2.12.1)
multi_json (~> 1.3)
has_scope (0.6.0.rc)
actionpack (>= 3.2, < 5)
activesupport (>= 3.2, < 5)
hashie (2.0.5)
hike (1.2.3)
httpauth (0.2.0)
i18n (0.6.5)
inherited_resources (1.4.1)
has_scope (~> 0.6.0.rc)
responders (~> 1.0.0.rc)
jbuilder (1.4.2)
activesupport (>= 3.0.0)
multi_json (>= 1.2.0)
jquery-rails (3.0.4)
railties (>= 3.0, < 5.0)
thor (>= 0.14, < 2.0)
jquery-ui-rails (4.0.4)
jquery-rails
railties (>= 3.1.0)
json (1.8.0)
jwt (0.1.8)
multi_json (>= 1.5)
kaminari (0.14.1)
actionpack (>= 3.0.0)
activesupport (>= 3.0.0)
libv8 (3.11.8.17)
mail (2.5.4)
mime-types (~> 1.16)
treetop (~> 1.4.8)
mime-types (1.23)
mini_portile (0.5.1)
minitest (4.7.5)
multi_json (1.7.9)
multi_test (0.0.2)
multipart-post (1.2.0)
nokogiri (1.6.0)
mini_portile (~> 0.5.0)
oauth2 (0.8.1)
faraday (~> 0.8)
httpauth (~> 0.1)
jwt (~> 0.1.4)
multi_json (~> 1.0)
rack (~> 1.2)
omniauth (1.1.4)
hashie (>= 1.2, < 3)
rack
omniauth-facebook (1.4.1)
omniauth-oauth2 (~> 1.1.0)
omniauth-mailru (1.0.0)
omniauth (~> 1.0)
omniauth-oauth2 (~> 1.0)
omniauth-oauth2 (1.1.1)
oauth2 (~> 0.8.0)
omniauth (~> 1.0)
omniauth-odnoklassniki (0.0.4)
omniauth (~> 1.0)
omniauth-oauth2 (~> 1.0)
omniauth-vkontakte (1.2.0)
multi_json
omniauth (~> 1.1.0)
omniauth-oauth2 (~> 1.0)
orm_adapter (0.4.0)
polyamorous (0.6.3)
activerecord (>= 3.0)
polyglot (0.3.3)
rack (1.5.2)
rack-test (0.6.2)
rack (>= 1.0)
rails (4.0.0)
actionmailer (= 4.0.0)
actionpack (= 4.0.0)
activerecord (= 4.0.0)
activesupport (= 4.0.0)
bundler (>= 1.3.0, < 2.0)
railties (= 4.0.0)
sprockets-rails (~> 2.0.0)
railties (4.0.0)
actionpack (= 4.0.0)
activesupport (= 4.0.0)
rake (>= 0.8.7)
thor (>= 0.18.1, < 2.0)
rake (10.1.0)
ransack (1.0.0)
actionpack (>= 3.0)
activerecord (>= 3.0)
polyamorous (~> 0.6.0)
rdiscount (2.1.6)
rdoc (3.12.2)
json (~> 1.4)
redis (3.0.4)
redis-actionpack (4.0.0)
actionpack (~> 4)
redis-rack (~> 1.5.0)
redis-store (~> 1.1.0)
redis-activesupport (4.0.0)
activesupport (~> 4)
redis-store (~> 1.1.0)
redis-rack (1.5.0)
rack (~> 1.5)
redis-store (~> 1.1.0)
redis-rails (4.0.0)
redis-actionpack (~> 4)
redis-activesupport (~> 4)
redis-store (~> 1.1.0)
redis-store (1.1.4)
redis (>= 2.2)
ref (1.0.5)
request_store (1.0.5)
responders (1.0.0.rc)
railties (>= 3.2, < 5)
rspec-core (2.14.5)
rspec-expectations (2.14.2)
diff-lcs (>= 1.1.3, < 2.0)
rspec-mocks (2.14.3)
rspec-rails (2.14.0)
actionpack (>= 3.0)
activesupport (>= 3.0)
railties (>= 3.0)
rspec-core (~> 2.14.0)
rspec-expectations (~> 2.14.0)
rspec-mocks (~> 2.14.0)
sass (3.2.10)
sass-rails (4.0.0)
railties (>= 4.0.0.beta, < 5.0)
sass (>= 3.1.10)
sprockets-rails (~> 2.0.0)
sdoc (0.3.20)
json (>= 1.1.3)
rdoc (~> 3.10)
simple_form (1.4.1)
simplecov (0.7.1)
multi_json (~> 1.0)
simplecov-html (~> 0.7.1)
simplecov-html (0.7.1)
slim (2.0.1)
temple (~> 0.6.6)
tilt (>= 1.3.3, < 2.1)
slim-rails (2.0.1)
actionpack (>= 3.0, < 4.1)
activesupport (>= 3.0, < 4.1)
railties (>= 3.0, < 4.1)
slim (~> 2.0)
spork (1.0.0rc3)
sprockets (2.10.0)
hike (~> 1.2)
multi_json (~> 1.0)
rack (~> 1.0)
tilt (~> 1.1, != 1.3.0)
sprockets-rails (2.0.0)
actionpack (>= 3.0)
activesupport (>= 3.0)
sprockets (~> 2.8)
sqlite3 (1.3.7)
temple (0.6.6)
therubyracer (0.11.4)
libv8 (~> 3.11.8.12)
ref
thor (0.18.1)
thread_safe (0.1.2)
atomic
tilt (1.4.1)
treetop (1.4.14)
polyglot
polyglot (>= 0.3.1)
turbolinks (1.3.0)
coffee-rails
tzinfo (0.3.37)
uglifier (2.1.2)
execjs (>= 0.3.0)
multi_json (~> 1.0, >= 1.0.2)
warden (1.2.3)
rack (>= 1.0)
xpath (2.0.0)
nokogiri (~> 1.3)
PLATFORMS
ruby
DEPENDENCIES
activeadmin!
annotate (>= 2.5.0)
cancan (= 1.6.10)
capybara
capybara-webkit
coffee-rails (~> 4.0.0)
cucumber
database_cleaner (< 1.1.0)
devise (= 3.0.2)
draper (~> 1.0)
factory_girl_rails
ffaker
formtastic!
jbuilder (~> 1.2)
jquery-rails (= 3.0.4)
kaminari (= 0.14.1)
omniauth (= 1.1.4)
omniauth-facebook
omniauth-mailru
omniauth-odnoklassniki
omniauth-vkontakte
rails (= 4.0.0)
rdiscount
redis-rails (~> 4.0.0)
rspec-rails (~> 2.0)
sass-rails (~> 4.0.0)
sdoc
simple_form (= 1.4.1)
simplecov
slim-rails (= 2.0.1)
spork-rails!
sqlite3
therubyracer
turbolinks (= 1.3.0)
uglifier (>= 1.3.0)

Answer 1

Require ActiveSupport:
require 'active_support/all'