validates_acceptance_of (ActiveRecord::Validations::ClassMethods)

    # File lib/active_record/validations.rb, line 425
          def validates_acceptance_of(*attr_names)
            configuration = { :message => ActiveRecord::Errors.default_error_messages[:accepted], :on => :save, :allow_nil => true, :accept => "1" }
            configuration.update(attr_names.extract_options!)

            db_cols = begin
              column_names
            rescue ActiveRecord::StatementInvalid
              []
            end
            names = attr_names.reject { |name| db_cols.include?(name.to_s) }
            attr_accessor(*names)

            validates_each(attr_names,configuration) do |record, attr_name, value|
              record.errors.add(attr_name, configuration[:message]) unless value == configuration[:accept]
            end
          end