pub.xml:xmlStringToXMLNode- classCast exception

Hi…
Can someone explain me the background of the xmlStringToXMLNode service, please? As i understand, the webmethods use default SOAP processor which is called in the background of the pub.xml:xmlStringToXMLNode service. Right?

I’m sometimes getting this error on calling xmlStringToXMLNode service:

SOAP-ENV:Envelope
xmlns:SOAP-ENV=“http://schemas.xmlsoap.org/soap/envelope/
xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance
xmlns:xsd=“http://www.w3.org/2001/XMLSchema”>
SOAP-ENV:Body
SOAP-ENV:Fault
SOAP-ENV:Server
[ISS.0088.9135] A WMDocument Exception was thrown in the server, usually because an XML block was not well-formed
http://schemas.xmlsoap.org/soap/actor/next

webM:serviceStackTrace
webM:javapub.soap.utils:streamToSoapData</webM:java>

webM:flowpub.client:soapHTTP</webM:flow>



webM:classNamejavax.xml.soap.SOAPException</webM:className>
<webM:message xml:lang="">[ISS.0088.9155] this SOAPMessage does not contain a valid Envelope object</webM:message>
<webM:stackTrace xml:lang="">javax.xml.soap.SOAPException: [ISS.0088.9155] this SOAPMessage does not contain a valid Envelope object
at com.wm.app.b2b.server.saaj.MessageFactory.createMessage(MessageFactory.java:55)
at pub.soap.utils.streamToSoapData(utils.java:984)

Thanks, Alex!