Using precondition names in XML

   Section 3.1.5 of RFC 3253 (DAV + versioning) says defines  
DAV:supported-report as:

     <!ELEMENT supported-report report>

   Which means it has to have exactly one report element.

   But DAV:supported-report is also used as the name of a  
precondition in section 3.6, which means that one should return this  
XML, according to 1.6.1:

<?xml version="1.0"?>
<D:error xmlns:D="DAV:">
  <D:supported-report/>
</D:error>

   Which is problematic since it uses an empty supported-report which  
is inconsistent with the element definition in 3.1.5.

   Am I reading this wrong?

   Also, I can't find an element definition for DAV:error in RFCs  
3253 or 2518.  Where is it defined?

     Thanks,
     -wsv