Implementation of STSClient

Hello.

Why is the class STSClient (org.apache.cxf.ws.security.trust.STSClient)
and its companion class AbstractSTSClient implemented "by hand" and not
e.g. using JAX-WS? The WSDL of the web service in question is available
(it's part of WS-Trust spec). So why create the request and read the
response "by hand" instead of using a typed interface to it?

AL