format.rb in aws-sdk-1.8.1

- old
+ new

@@ -1,6 +1,6 @@
-# Copyright 2011-2012 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# Copyright 2011-2013 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"). You
 # may not use this file except in compliance with the License. A copy of
 # the License is located at
 #
@@ -19,10 +19,10 @@
     # @private
     class FormatValidator < Validator
 
       ACCEPTED_OPTIONS = [
         :with, :without, 
-        :message, :allow_nil, :on, :if, :unless,
+        :message, :allow_nil, :allow_blank, :on, :if, :unless,
       ]
 
       def setup record_class
         ensure_type(Regexp, :with, :without)
         ensure_at_least_one(:with, :without)