DataSet Class in Silverlight

Question

hello guys how r u all ?

my question is that, i am creating login form in silverlight with database connectivity, i am retriveing data from service with Dataset class but in silverlight page.xaml.cs  there is no access for DataSet class which is in System.Data Namespace, so please tell me how can i access System.Data Namespace in page.xaml.cs  Page in silverlight 



please Reply Soon 


Thanks.