Ruby loading libs (RSS)

I’m following the instructions here;name=RSS+Parser%3A%3AREADME.en
to update RSS.

When I run RSS::VERSION in irb, it gives me
irb(main):003:0> require ‘rss’
=> true
irb(main):004:0> RSS::VERSION
=> “0.1.6”

But if I sudo -s, it gives me
irb(main):002:0> RSS::VERSION
=> “0.2.3”

Is there any difference between running irb under sudo or not? Is there
a config I can set to determine which libs to load?

Besides using RSS, are there other recommended ways to parse RSS feeds?

Thanks in advance.

If anyone has the same problem, the load paths where listed in different
orders - /usr/local/lib/site_ruby/1.8 and /usr/lib/ruby/1.8 were
reversed under root. I fixed it by removing rss files under