it is actually a bug from my point of view.
The deal is, that if a binding has named "binding", the project is not compiled.
<wsdl:binding name="binding" type="tns:Z_SCWM_KPI2_WS">
<wsp:Policy>
<wsp:PolicyReference URI="#BN_BN_binding" />
</wsp:Policy>
<soap:binding style="document"
<wsdl:operation name="Z_SCWM_KPI2_RETURN">
<soap:operation style="document" soapAction="" />
<wsdl:input>
<soap:body use="literal" />
</wsdl:input>
<wsdl:output>
<soap:body use="literal" />
</wsdl:output>
</wsdl:operation>
</wsdl:binding>
<wsdl:service name="Z_SCWM_KPI2_WS">
<wsdl:port binding="tns:binding" name="binding">
<soap:address location="http://...../z_scwm_kpi2_ws/binding" />
</wsdl:port>
</wsdl:service>