default writing the schema file as utf-8

activerecord/lib/active_record/railties/databases.rake

@@ -341,7 +341,8 @@ db_namespace = namespace :db do
     desc 'Create a db/schema.rb file that can be portably used against any DB supported by AR'
     task :dump => :load_config do
       require 'active_record/schema_dumper'
-      File.open(ENV['SCHEMA'] || "#{Rails.root}/db/schema.rb", "w") do |file|
+      filename = ENV['SCHEMA'] || "#{Rails.root}/db/schema.rb"
+      File.open(filename, "w:utf-8") do |file|
         ActiveRecord::Base.establish_connection(Rails.env)
         ActiveRecord::SchemaDumper.dump(ActiveRecord::Base.connection, file)
       end