Simon catches me in a small gaffe. Indeed, the QName of the root element is what really matters.

However, I don't think I'm understood. I don't mean, "how do I tell that a piece of XML is a SOAP message", but given any SOAP message, how I tell the "type" of that SOAP message? In otherwords, what

• message in which
  
• operation of what
  
• portType in which
  
• WSDL?