Testing RSS feeds on functional tests (yet another question)

Is there any commonly used way to test RSS feeds and/or XML output?
I have done my research and found those two links

http://lists.rubyonrails.org/pipermail/rails/2006-August/062267.html

My first attempts were to use assert_tag directly. I knew the response
body
wouldn’t be XHTML, but thought the parser would deal happily with
well-formed
XML. It turns out it doesn’t.

It seems to not like the tag that is mandatory in RSS 2.0. The
message I
get is something along the lines of ‘ignoring attempt to close channel
with link’,
but the XML is well formed.

The guy on the message and blog post above proposes a solution to
another
problem (namely asserting against other XML data sources) and it
doesn’t
seem to apply to mine. I have no problem with asserting against the
response
body only, but I need to use a parser that recognizes RSS or at least
XML.

Before I proceed to write my assertions using some XML processing lib,
I need to
ask how are you guys testing your RSS feeds?

Cheers,

Thiago A.