With Ruby 1.9.2-p290, the following encoding error occurs...

gems/feedtools-0.2.29/lib/feed_tools/helpers/uri_helper.rb:43: invalid multibyte char (US-ASCII)
gems/feedtools-0.2.29/lib/feed_tools/helpers/uri_helper.rb:43: syntax error, unexpected $end, expecting ')'
          if IDN::Idna.toASCII('http://www.詹▒▒.com/') ==

To fix, the following line needs to be added to the top of uri_helper.rb:
# encoding: UTF-8