Problem report

Hi there,

I'm trying to parse a simple rdf+xml document, which I believe is 
valid (or at the very least isn't insane). I get the following when 
asking for validation, showing triples only (no graph):

Parser Loading Error

Exception parsing: java.lang.NullPointerException 

The RDF XML in question is:

<?xml version="1.0" encoding="UTF-8"?>
<rdf:RDF
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns="http://purl.org/rss/1.0/"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:enc="http://purl.oclc.org/net/rss_2.0/enc#">
    <channel 
rdf:about="http://www.sussex.ac.uk/newsandevents/sussexlectures/rss.xml">
        <title>Sussex Lectures</title>
        <link>http://www.sussex.ac.uk/newsandevents/sussexlectures</link>
        <description>Throughout the year, the University of Sussex 
is host to an exciting series of public lectures that       
illustrate the breadth and quality of research being conducted at 
the University</description>                                         
<items>                                                                                                                            
<rdf:Seq>
                <rdf:li 
resource="http://www.sussex.ac.uk/newsandevents/sussexlectures/cummings.php" 
/>
            </rdf:Seq>
        </items>
        <dc:rights>Copyright University of Sussex</dc:rights>
    </channel>

    <item 
rdf:about="http://www.sussex.ac.uk/newsandevents/sussexlectures/cummings.php">
        <title>Professorial Lecture: No love for the Jewish 
people?</title>
        <link>http://www.sussex.ac.uk/newsandevents/sussexlectures/cummings.php</link>
        <dc:creator>Professor Christian Weise, Professor of Jewish 
History</dc:creator>
        <dc:date>2009-11-25</dc:date>                                                                                                  
<enc:enclosure 
rdf:resource="http://www.sussex.ac.uk/video/sussexlectures/audio/cummings.mp3">                                     
<dc:type>Sound</dc:type>
        </enc:enclosure>                                                                                                               
<enc:enclosure 
rdf:resource="rtsp://streaming.sussex.ac.uk/video/sussexlectures/christianwiese.mov" 
/>                     
</item>                                                                                                                                                                                                                                                       
<!-- so, can we have these as children of enc:enclosure declarations 
above? -->                                                
<enc:Enclosure 
rdf:about="http://www.sussex.ac.uk/video/sussexlectures/audio/cummings.mp3">                                    
</enc:Enclosure>                                                                                                               
<enc:Enclosure 
url="rtsp://streaming.sussex.ac.uk/video/sussexlectures/christianwiese.mov">
        <dc:type>MovingImage</dc:type>
    </enc:Enclosure>
</rdf:RDF>


P.S. Also, the "Submit problem report" button on your error form 
didn't appear to do anything.