Am I using webserviceNew() correctly or is this a bug?

This:

mywebservice = webserviceNew('https://wsdl.site.com');
writeDump(var=mywebservice);

…threw this error on the writeDump:

cannot convert response with mime type [text/html; charset=UTF-8] to a CFML Object

…so I reverted to:

mywebservice = createObject('webservice', 'https://wsdl.site.com');
writeDump(var=mywebservice);

…and that worked fine. Am I not using webserviceNew correctly or is this a bug?