diff --git a/railties/CHANGELOG b/railties/CHANGELOG
index eb18007d300086991d334792ee05f3df250180f4..634caf4ffb39bd1712122852776d71d0b1f5e967 100644
--- a/railties/CHANGELOG
+++ b/railties/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Set $KCODE to 'u' by default to enable the multibyte safe String#chars proxy. [Koz]
+
 * Added config.plugins to control which plugins are loaded #6269 [skaes]. By default, everything in vendor/plugins will be loaded, but if you specify config.plugins, only those will be loaded. Example:
 
     config.plugins = %w[ routing_navigator simply_helpful ]
diff --git a/railties/lib/initializer.rb b/railties/lib/initializer.rb
index 1400930768430bc8959863d569b25c604208d9c0..ba651a2a035e7c714817344c021e8b5d1eeb83ee 100644
--- a/railties/lib/initializer.rb
+++ b/railties/lib/initializer.rb
@@ -83,6 +83,7 @@ def process
       set_autoload_paths
       load_environment
 
+      initialize_encoding
       initialize_database
       initialize_logger
       initialize_framework_logging
@@ -197,6 +198,13 @@ def load_observers
       ActiveRecord::Base.instantiate_observers
     end
 
+    # This initialzation sets $KCODE to 'u' to enable the multibyte safe operations.
+    # Plugin authors supporting other encodings should override this behaviour and 
+    # set the relevant +default_charset+ on ActionController::Base
+    def initialize_encoding
+      $KCODE='u'
+    end
+
     # This initialization routine does nothing unless <tt>:active_record</tt>
     # is one of the frameworks to load (Configuration#frameworks). If it is,
     # this sets the database configuration from Configuration#database_configuration