Brad,

Just to give a little more info to you for the problem feed,

The RSS v2.0 spec lists the following info regarding the enclosure element:

<enclosure> sub-element of <item> 

<enclosure> is an optional sub-element of <item>.

It has three required attributes. url says where the enclosure is located, length says how big it is in bytes, and type says what its type is, a standard MIME type.

The url must be an http url.

<enclosure url="http://www.scripting.com/mp3s/weatherReportSuite.mp3" length="12216320" type="audio/mpeg" />

 

Looking at one of the items I find an example:

  <item>
   <title>ENERGY STAR In Your Office</title>
   <link>http://downloads.energystar.gov/dl_00006/PM_6-25_EDITsmall.mov</link>
   <description><![CDATA[Learn how ENERGY STAR qualified computers and monitors and other office equipment can save you energy, money, and help protect the environment. Also learn how to get the most energy and money savings from your computer by enabling the power management features on your models. Use this video to help educate your employees and customers!]]></description>
   <category>podcasts</category>
   <pubDate>Fri, 05 Sep 2008 12:01:00 GMT</pubDate>
   <guid isPermaLink="true">http://downloads.energystar.gov/dl_00006/PM_6-25_EDITsmall.mov</guid>
   <enclosure url="http://downloads.energystar.gov/dl_00006/PM_6-25_EDITsmall.mov" type="audio/mpeg"/>
   <itunes:author>ENERGY STAR</itunes:author>
   <itunes:explicit>No</itunes:explicit>
  </item>
 

In the enclosure element the missing required attribute 'length' is not found, and apparently is the source of the error.  Now, we can't always change the news feed source, so the other option is to use the XML/XSL if you cannot make the correction to the news feed source.