diff --git a/activemodel/lib/active_model/validations/exclusion.rb b/activemodel/lib/active_model/validations/exclusion.rb
index 0a44c6d54f..7ee718cf3c 100644
--- a/activemodel/lib/active_model/validations/exclusion.rb
+++ b/activemodel/lib/active_model/validations/exclusion.rb
@@ -2,7 +2,6 @@ module ActiveModel
   module Validations
     class ExclusionValidator < EachValidator
       def check_validity!
-        options[:in] ||= options.delete(:within)
         raise ArgumentError, "An object with the method include? is required must be supplied as the " <<
                              ":in option of the configuration hash" unless options[:in].respond_to?(:include?)
       end
diff --git a/activemodel/lib/active_model/validations/inclusion.rb b/activemodel/lib/active_model/validations/inclusion.rb
index 25b8c7866d..0c1334fe1b 100644
--- a/activemodel/lib/active_model/validations/inclusion.rb
+++ b/activemodel/lib/active_model/validations/inclusion.rb
@@ -2,7 +2,6 @@ module ActiveModel
   module Validations
     class InclusionValidator < EachValidator
       def check_validity!
-          options[:in] ||= options.delete(:within)
          raise ArgumentError, "An object with the method include? is required must be supplied as the " <<
                               ":in option of the configuration hash" unless options[:in].respond_to?(:include?)
        end
diff --git a/activemodel/lib/active_model/validations/length.rb b/activemodel/lib/active_model/validations/length.rb
index f41ce34328..871f589af9 100644
--- a/activemodel/lib/active_model/validations/length.rb
+++ b/activemodel/lib/active_model/validations/length.rb
@@ -1,36 +1,43 @@
 module ActiveModel
   module Validations
     class LengthValidator < EachValidator
-      OPTIONS   = [ :is, :within, :in, :minimum, :maximum ].freeze
       MESSAGES  = { :is => :wrong_length, :minimum => :too_short, :maximum => :too_long }.freeze
       CHECKS    = { :is => :==, :minimum => :>=, :maximum => :<= }.freeze
 
       DEFAULT_TOKENIZER = lambda { |value| value.split(//) }
-      attr_reader :type
 
       def initialize(options)
-        @type = (OPTIONS & options.keys).first
+        if range = (options.delete(:in) || options.delete(:within))
+          raise ArgumentError, ":in and :within must be a Range" unless range.is_a?(Range)
+          options[:minimum], options[:maximum] = range.begin, range.end
+          options[:maximum] -= 1 if range.exclude_end?
+        end
+
         super(options.reverse_merge(:tokenizer => DEFAULT_TOKENIZER))
       end
 
       def check_validity!
-        ensure_one_range_option!
-        ensure_argument_types!
+        keys = CHECKS.keys & options.keys
+
+        if keys.empty?
+          raise ArgumentError, 'Range unspecified. Specify the :within, :maximum, :minimum, or :is option.'
+        end
+
+        keys.each do |key|
+          value = options[key]
+
+          unless value.is_a?(Integer) && value >= 0
+            raise ArgumentError, ":#{key} must be a nonnegative Integer"
+          end
+        end
       end
         
       def validate_each(record, attribute, value)
-        checks = options.slice(:minimum, :maximum, :is)
-        value  = options[:tokenizer].call(value) if value.kind_of?(String)
+        value = options[:tokenizer].call(value) if value.kind_of?(String)
 
-        if [:within, :in].include?(type)
-          range = options[type]
-          checks[:minimum], checks[:maximum] = range.begin, range.end
-          checks[:maximum] -= 1 if range.exclude_end?
-        end
-
-        checks.each do |key, check_value|
+        CHECKS.each do |key, validity_check|
+          next unless check_value = options[key]
           custom_message = options[:message] || options[MESSAGES[key]]
-          validity_check = CHECKS[key]
 
           valid_value = if key == :maximum
             value.nil? || value.size.send(validity_check, check_value)
@@ -38,33 +45,8 @@ def validate_each(record, attribute, value)
             value && value.size.send(validity_check, check_value)
           end
 
-          record.errors.add(attribute, MESSAGES[key], :default => custom_message, :count => check_value) unless valid_value
-        end
-      end
-
-    protected
-
-      def ensure_one_range_option! #:nodoc:
-        range_options = OPTIONS & options.keys
-
-        case range_options.size
-        when 0
-          raise ArgumentError, 'Range unspecified. Specify the :within, :maximum, :minimum, or :is option.'
-        when 1
-          # Valid number of options; do nothing.
-        else
-          raise ArgumentError, 'Too many range options specified. Choose only one.'
-        end
-      end
-    
-      def ensure_argument_types! #:nodoc:
-        value = options[type]
-
-        case type
-        when :within, :in
-          raise ArgumentError, ":#{type} must be a Range" unless value.is_a?(Range)
-        when :is, :minimum, :maximum
-          raise ArgumentError, ":#{type} must be a nonnegative Integer" unless value.is_a?(Integer) && value >= 0
+          next if valid_value
+          record.errors.add(attribute, MESSAGES[key], :default => custom_message, :count => check_value)
         end
       end
     end
diff --git a/activemodel/test/cases/validations/length_validation_test.rb b/activemodel/test/cases/validations/length_validation_test.rb
index f3ef5e648a..99d0268b67 100644
--- a/activemodel/test/cases/validations/length_validation_test.rb
+++ b/activemodel/test/cases/validations/length_validation_test.rb
@@ -221,10 +221,8 @@ def test_validates_length_of_using_bignum
   end
 
   def test_validates_length_of_nasty_params
-    assert_raise(ArgumentError) { Topic.validates_length_of(:title, :minimum=>6, :maximum=>9) }
-    assert_raise(ArgumentError) { Topic.validates_length_of(:title, :within=>6, :maximum=>9) }
-    assert_raise(ArgumentError) { Topic.validates_length_of(:title, :within=>6, :minimum=>9) }
-    assert_raise(ArgumentError) { Topic.validates_length_of(:title, :within=>6, :is=>9) }
+    assert_raise(ArgumentError) { Topic.validates_length_of(:title, :is=>-6) }
+    assert_raise(ArgumentError) { Topic.validates_length_of(:title, :within=>6) }
     assert_raise(ArgumentError) { Topic.validates_length_of(:title, :minimum=>"a") }
     assert_raise(ArgumentError) { Topic.validates_length_of(:title, :maximum=>"a") }
     assert_raise(ArgumentError) { Topic.validates_length_of(:title, :within=>"a") }