Problem using WSDL service from Python, it is my client code or the server?

Question

I'm trying to write a Python client for a a WSDL service. I'm using the Suds library to handle the soap messages. When I try to call the service, I get a suds exception: <rval /> not mapped to message part. If I set the retxml suds option I get XML which looks OK to me.

Is the problem with the client code? Am I missing some flag which will allow Suds to correctly parse the XML? Alternatively, the problem could be with the server. Is the XML not structured correctly?

Thanks, Dan

My code is a follows (method names changed):

c = Client(url)  
p = c.factory.create('MyParam')  
p.value = 100  
c.service.run(p)  

This results in a suds exception:

File "/home/.../test.py", line 38, in test  
res = self.client.service.run(p)
File "/usr/local/lib/python2.6/dist-packages/suds-0.3.9-py2.6.egg/suds/client.py", line 539, in __call__
return client.invoke(args, kwargs)
File "/usr/local/lib/python2.6/dist-packages/suds-0.3.9-py2.6.egg/suds/client.py", line 598, in invoke
result = self.send(msg)
File "/usr/local/lib/python2.6/dist-packages/suds-0.3.9-py2.6.egg/suds/client.py", line 627, in send  
result = self.succeeded(binding, reply.message)  
File "/usr/local/lib/python2.6/dist-packages/suds-0.3.9-py2.6.egg/suds/client.py", line   659, in succeeded  
r, p = binding.get_reply(self.method, reply)  
File "/usr/local/lib/python2.6/dist-packages/suds-0.3.9-py2.6.egg/suds/bindings/binding.py", line 151, in get_reply  
result = self.replycomposite(rtypes, nodes)  
File "/usr/local/lib/python2.6/dist-packages/suds-0.3.9-  py2.6.egg/suds/bindings/binding.py", line 204, in replycomposite  
raise Exception('<%s/> not mapped to message part' % tag)  
Exception: <rval/> not mapped to message part  

The returned XML (modified to remove customer identifiers)

<S:Envelope xmlns:S="http://schemas.xmlsoap.org/soap/envelope/"&gt;
  <S:Body>
    <ns2:getResponse xmlns:ns2="http://api.xxx.xxx.com/api/"&gt;
      <rval xmlns="http://xxx.xxx.xxx.com/api/"&gt;
        <ns2:totalNumEntries>
          2
        </ns2:totalNumEntries>
        <ns2:entries>
          <ns2:id>
            1
          </ns2:id>
        </ns2:entries>
        <ns2:entries>
          <ns2:id>
            2
          </ns2:id>
        </ns2:entries>
      </rval>
    </ns2:getResponse>
  </S:Body>
</S:Envelope>