    # File lib/ramaze/helper/gravatar.rb, line 63
          def gravatar(email, opts = {})
            uri = URI("http://www.gravatar.com/")
            ext = opts[:ext]
            uri.path = "/avatar/#{Digest::MD5.hexdigest(email.to_str)}#{ext}"

            query = {}
            query[:size]    = opts[:size].to_i.to_s if opts.key?(:size)
            query[:rating]  = opts[:rating].to_s if opts.key?(:rating)
            query[:default] = opts[:default].to_s if opts.key?(:default)
            query[:force]   = '1' if opts[:force]

            uri.query = Rack::Utils.build_query(query) if query.any?
            uri
          end