diff --git a/Gemfile b/Gemfile
index ad89c2a..ea12762 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,5 @@
-source "http://rubygems.org"
+source :rubygems
 
-# Specify your gem's dependencies in http_accept_language.gemspec
 gemspec
+gem "test-unit", ">=2.5.1"
+gem "rake"
diff --git a/lib/http_accept_language.rb b/lib/http_accept_language.rb
index f1110ee..275ef7f 100644
--- a/lib/http_accept_language.rb
+++ b/lib/http_accept_language.rb
@@ -55,11 +55,48 @@ def compatible_language_from(available_languages)
     end.compact.first
   end
 
+  # Returns a supplied list of available locals without any extra application info
+  # that may be attached to the locale for storage in the application.
+  #
+  # Example:
+  # [ja_JP-x1, en-US-x4, en_UK-x5, fr-FR-x3] => [ja-JP, en-US, en-UK, fr-FR]
+  #
+  def sanitize_available_locales(available_languages)
+    available_languages.map do |avail|
+      split_locale = avail.split(/[_-]/)
+
+      split_locale.map do |e|
+        e unless e.match(/x|[0-9*]/)
+      end.compact.join("-")
+    end
+  end
+
+  # Returns the first of the user preferred languages that is
+  # also found in available languages.  Finds best fit by matching on
+  # primary language first and secondarily on region.  If no matching region is
+  # found, return the first language in the group matching that primary language.
+  #
+  # Example:
+  #
+  #   request.language_region_compatible(available_languages)
+  #
+  def language_region_compatible_from(available_languages)
+    available_languages = sanitize_available_locales(available_languages)
+    user_preferred_languages.map do |x| #en-US
+      lang_group = available_languages.select do |y| # en
+        y = y.to_s
+        x.split('-', 2).first == y.split('-', 2).first
+      end
+      lang_group.find{|l| l == x} || lang_group.first #en-US, en-UK
+    end.compact.first
+  end
 end
-if defined?(ActionDispatch::Request)
-  ActionDispatch::Request.send :include, HttpAcceptLanguage
-elsif defined?(ActionDispatch::AbstractRequest)
-  ActionDispatch::AbstractRequest.send :include, HttpAcceptLanguage
-elsif defined?(ActionDispatch::CgiRequest)
-  ActionDispatch::CgiRequest.send :include, HttpAcceptLanguage
+
+if defined?(ActionPack)
+  classes = if ActionPack::VERSION::MAJOR == 2
+    [ActionController::Request, ActionController::CgiRequest]
+  else
+    [ActionDispatch::Request]
+  end
+  classes.each{|c| c.send :include, HttpAcceptLanguage }
 end
diff --git a/rails/init.rb b/rails/init.rb
deleted file mode 100644
index 7d3dba1..0000000
--- a/rails/init.rb
+++ /dev/null
@@ -1 +0,0 @@
-require "http_accept_language"
diff --git a/test/http_accept_language_test.rb b/test/http_accept_language_test.rb
index 41c47fd..315252a 100644
--- a/test/http_accept_language_test.rb
+++ b/test/http_accept_language_test.rb
@@ -2,6 +2,24 @@
 require 'http_accept_language'
 require 'test/unit'
 
+module ActionPack
+  module VERSION
+    MAJOR = 3
+  end
+end
+
+module ActionDispatch
+  class Request
+  end
+end
+
+module ActionController
+  class CgiRequest
+  end
+  class Request
+  end
+end
+
 class MockedCgiRequest
   include HttpAcceptLanguage
   def env
@@ -37,13 +55,48 @@ def test_should_find_first_compatible_from_user_preferred
     request.env['HTTP_ACCEPT_LANGUAGE'] = 'en-us,de-de'
     assert_equal 'en', request.compatible_language_from(%w{de en})
   end
-  
+
   def test_should_accept_symbols_as_available_languages
     request.env['HTTP_ACCEPT_LANGUAGE'] = 'en-us'
     assert_equal :"en-HK", request.compatible_language_from([:"en-HK"])
   end
 
+  def test_should_sanitize_available_language_names
+    assert_equal ["en-UK", "en-US", "ja-JP", "pt-BR"], request.sanitize_available_locales(%w{en_UK-x3 en-US-x1 ja_JP-x2 pt-BR-x5})
+  end
+
+  def test_should_find_most_compatible_language_from_user_preferred
+    request.env['HTTP_ACCEPT_LANGUAGE'] = 'ja,en-gb,en-us,fr-fr'
+    assert_equal "ja-JP", request.language_region_compatible_from(%w{en-UK en-US ja-JP})
+  end
+
+  def test_should_be_included_into_actionpack_v2
+    silence_warnings do
+      ActionPack::VERSION.const_set(:MAJOR, 2)
+    end
+    load "http_accept_language.rb"
+
+    assert_include ActionController::Request.ancestors, HttpAcceptLanguage
+    assert_include ActionController::CgiRequest.ancestors, HttpAcceptLanguage
+  end
+
+  def test_should_be_included_into_actionpack_v3
+    silence_warnings do
+      ActionPack::VERSION.const_set(:MAJOR, 3)
+    end
+    load "http_accept_language.rb"
+    assert_include ActionDispatch::Request.ancestors, HttpAcceptLanguage
+  end
+
   private
+
+  def silence_warnings
+    old_verbose, $VERBOSE = $VERBOSE, nil
+    yield
+  ensure
+    $VERBOSE = old_verbose
+  end
+
   def request
     @request ||= MockedCgiRequest.new
   end