Warning parenthesize argument scrubyt

Hi
I’ve follow the scrubyt tutorial for installation then I found
examples into github GitHub - scrubber/scrubyt_examples: A handful (but hopefully growing amount) of scRUBYt! examples but
when I compile that example compare this warning

/ruby/lib/gems/1.8/gems/nokogiri-1.4.0-x86-mswin32/lib/nokogiri/xml/
builder.rb:272: warning : parenthesize argument(s) for future version

and then nothing else happens

someone can help me?