questions about DOMConfiguration

[Francesc Guim Bernat]

Hello,
   i'm having some problems using the lcass DOMConfiguration, i've been 
trying different possibilities ... but it never works. I wanna assing 
dynamically the associated XML Schema of a document, all the times i'm 
getting an error NOT_SUPPORTED_ERR. I think that i'm using the correct 
values coz that values are the provided values in the DOMConfiguration 
documentation.
The pice of code is:

           DOMConfiguration *  configuracio = 
this->document->getDOMConfiguration();

           XMLCh* schema_type = 
XMLString::transcode("http://www.w3.org/2001/XMLSchema\0";);
           XMLCh* type = XMLString::transcode("schema-type");
          
           XMLCh* schema_location = XMLString::transcode(XsdPath);
           XMLCh* location = XMLString::transcode("schema-location\0");

           const void* d = configuracio->getParameter(type); //just for 
check
           const void* e = configuracio->getParameter(location); //just 
for chek

           configuracio->setParameter(type,schema_type);
           configuracio->setParameter(location,schema_location);
           //abans d'assignar l'XML Schema cal validar que el motor de 
la llibreria l'accepta
           if(configuracio->canSetParameter(type,schema_type) &&
               configuracio->canSetParameter(location,schema_location))
           {
               configuracio->setParameter(type,schema_type);
               configuracio->setParameter(location,schema_location);
           }
           else
               return false;

the d and e values are always null.  What i'm doing wrong ?
Thanks a lot !!!
Francesc Guim Bernat