如何在silverlight中获取日期时间？

from title it appears a stupid question :) i know but i have a silverlight application that needs to send datetime to a 3rdparty web method and based on datetime populate some client side controls... now i know how to get datetime from client but problem is that client time could be wrong........ one method is to use a webservice to get datetime any other idea?from title it appears a stupid question :) i kn