Help desgining auto-updating RSS feed

I have a Perl script that creates a new version of this file every hour. But I’ve tried two RSS readers and they’re not receiving the updates. What do you suggest?

<?xml version="1.0" encoding="UTF-8"?>

<rss version="2.0" 
<title>Test News Feed</title>
<description>News feed for testing</description>
<pubDate>Thu, 18 Feb 2010 17:00:02 -0500</pubDate>
<lastBuildDate>Thu, 18 Feb 2010 17:00:02 -0500</lastBuildDate>
<title>Lastest test feed</title>
<description>Summary of latest test</description>
<guid isPermaLink="true"></guid>
<pubDate>Thu, 18 Feb 2010 17:00:02 -0500</pubDate>

You should start by trying to find where the problem resides, by making sure the file itself is changing then looking into the rss readers. More information could help lead to a solution from other forum members.

I’ve checked several times and the file updates each hour. (I have a cronjob running for that purpose.) Which RSS readers do you suggest for testing? I was using Google Reader but I have to click Refresh to get the updated feed. RSS Ticker for Firefox would only auto-update for other feeds I had in Live Bookmarks but not my own.