The WSDL is in rpc/encoded format; SOAP::WSDL currently only understands the document/literal format. It's possible (although unlikely) that the SOAP server to which you wish to send requests is capable of parsing messages in both formats, in which case you'd need to convert that WSDL to a valid document/literal file and then run it through wsdl2perl.pl. I'd recommend checking with the vendor before going down that road, tho; no sense it writing a conversion script if they can't support the request.
--n