Xerces can't parse Voice XML schema

Hi All,
    I want to parse the "test.xml" file with following contents. 

<?xml version="1.0" encoding="UTF-8"?> 
<vxml xmlns="http://www.w3.org/2001/vxml" 
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
  xsi:schemaLocation="http://www.w3.org/2001/vxml 
   http://www.w3.org/TR/voicexml20/vxml.xsd"
   version="2.0">
  <form>
    <block>Hello World!</block>
  </form>
</vxml>

I have downloaded the current binary Releases of Xerces-C for Windows 2000 .
I tried to parse it using "PParse -n -s test.xml"
But I failed, Errors which are printed are,
Error at file http://www.w3.org/TR/voicexml20/vxml-synthesis-restriction.xsd, li
ne 30, char 53
  Message: Could not find a declaration in the schema to be redefined correspond
ing to 'say-as'

Error at file http://www.w3.org/TR/voicexml20/vxml-synthesis-restriction.xsd, li
ne 43, char 52
  Message: Could not find a declaration in the schema to be redefined correspond
ing to 'audio'

Error at file http://www.w3.org/TR/voicexml20/vxml-synthesis-extension.xsd, line
 30, char 53
  Message: Global complexType:'say-as' declared more than once or also declared
as simpleType

Error at file http://www.w3.org/TR/voicexml20/vxml-synthesis-extension.xsd, line
 43, char 52
  Message: Global complexType:'audio' declared more than once or also declared as
 simpleType

I think the files are right, so maybe Xerces got problems ?
I am using  "PParse -n -s test.xml"

 
Thanks,
VaraPrasad V