[xml] Schemas parser error: when using libxml2 to parse the schema of SOAP 1.2

[Gloria Yang <gloriayang yang gmail com>]

Dear all:

I am using libxml2 with the schema of SOAP1.2 to validate SOAP message
http://www.w3.org/2002/12/soap-envelope/

And I got an error message like:
*****************************************************************************
soap2002.xsd:88: element field: Schemas parser error :
Element '{ http://www.w3.org/2001/XMLSchema}field',
attribute 'xpath': The XPath _expression_ '@xml:lang' could not be compiled.
*****************************************************************************

Is there anything wrong?
What should I do?
Any suggestion is appreciated.

BRs.
Gloria