PHP webservice SOAPClient error

Question

Hello,

I have a webserivce and just doing simple thing to call webservice in SOAP Client

i.e.

$client = new SoapClient("http://test.unistream.com/wcflib/service.svc?WSDL");

It says

SOAP-ERROR: Parsing WSDL: 'IWebService_GetCountries_InputMessage' already defined

web service is

http://test.unistream.com/wcflib/service.svc?WSDL

Thanks.