Merge branch 'master' into active_model

Conflicts:
	activemodel/lib/active_model/core.rb
	activemodel/test/cases/state_machine/event_test.rb
	activemodel/test/cases/state_machine/state_transition_test.rb
	activerecord/lib/active_record/validations.rb
	activerecord/test/cases/validations/i18n_validation_test.rb
	activeresource/lib/active_resource.rb
	activeresource/test/abstract_unit.rb

1 files changed, 2 insertions, 1 deletions

diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index c2bde29895..4be91d0505 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -41,9 +41,10 @@ module ActiveModel
     end
 
     def to_xml(options={})
+      require 'builder' unless defined? ::Builder
       options[:root]    ||= "errors"
       options[:indent]  ||= 2
-      options[:builder] ||= Builder::XmlMarkup.new(:indent => options[:indent])
+      options[:builder] ||= ::Builder::XmlMarkup.new(:indent => options[:indent])
 
       options[:builder].instruct! unless options.delete(:skip_instruct)
       options[:builder].errors do |e|