Switch to_xml to use the date formate defined in xml schema.[Koz]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3869 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

 *SVN*
 
+* Switched to_xml to use the xml schema format for datetimes.  This allows the encoding of time zones and should improve operability. [Koz]
+
 * Added a note to the documentation for the Date related Numeric extensions to indicate that they're
 approximations and shouldn't be used for critical calculations. [Koz]
 

activesupport/lib/active_support/core_ext/hash/conversions.rb

@@ -12,7 +12,7 @@ module Conversions
         
         XML_FORMATTING = {
           "date"     => Proc.new { |date| date.to_s(:db) },
-          "datetime" => Proc.new { |time| time.to_s(:db) }
+          "datetime" => Proc.new { |time| time.xmlschema }
         }
         
         def to_xml(options = {})