What version of the XML adapter are you using? If it is the 4.2 version, then I know there is a Namespaces tab for both the parse and generate operations. I believe that will get you the Namespace elements that you need.
The type requirements on the other hand I’m not sure if or how this is supported by the generateXML operation. I don’t think modification of the XSD will get you what you need.
You may end up having to build the XML yourself in custom code which defeats the whole purpose of using the XML adapter in the 1st place. It has always been one of the weaker adapter implementations provided by webMethods.