Null was error message when uploaded the XML into RQM

When uploaded the XML file into RQM, the error message is NULL.  May I know what is the missing below?  Thank you so much.

<?xml version="1.0"?>
<requirement xmlns="http://jazz.net/xmlns/alm/qm/v0.1/">
 <title>Testing</title>
 <description>First Testing</description>
 <updated>
 <state>authoring.s1</state>
 <creator>ADMIN</creator>
 <owner>UNASSIGNED</owner>
 <resolver>ADMIN</resolver>
 <priority></priority>
 <reviewStatus></reviewStatus>
 <suspectStatus></suspectStatus>
 <creationtime>2010-09-18 09:00:00</creationtime>
 <resolutionTime></resolutionTime>
 <externalTag>1.01a</externalTag>
 <approvals>1</approvals>
 <customAttributes>1</customAttributes>
 <risk>1</risk>
 </updated>
</requirement>