If you need to send a date parameter to a Web Service using Ruby and SOAP:WSDLDriver then be sure to use the DateTime object. I just spent two mind-numbing hours trying to figure out why it wouldn’t accept my param.
e.g.
dateToUse = DateTime.civil(2005, 1, 1, 1, 1, 1) soapResponse = soap.GetNewTagsSince(:sinceDate => dateToUse)