module Jekyll
  module Commands
    class Serve

      class << self
        alias :_original_webrick_options :webrick_options
      end

      def self.webrick_options(config)
        options = _original_webrick_options(config)
        options[:MimeTypes].merge!({'html' => 'text/html; charset=utf-8'})
        options[:MimeTypes].merge!({'xml'  => 'text/xml; charset=utf-8'})
        options
      end

    end
  end
end

Set RSS to serve UTF8 information
Set RSS to serve UTF8 information