Currently if a service is "document" style the wsdl message looks like so:
<wsdl:message name="doSomethingRequest">
<wsdl:part element="xsd:string" name="a"/>
<wsdl:part element="xsd:string" name="b"/>
</wsdl:message>
This is quite ambiguos for client toolkits. These should reference concrete schema types instead.
http://www.ws-i.org/Profiles/BasicProfile-1.1-2004-08-24.html#Declaration_of_part_Elements