AdminServices.AdminSoapClient x = new AdminServices.AdminSoapClient();
x.ClientCredentials.Windows.ClientCredential = new NetworkCredential(userName, pwd);
x.ClientCredentials.Windows.AllowedImpersonationLevel = System.Security.Principal.TokenImpersonationLevel.Impersonation;
//x.ClientCredentials.Windows.AllowNtlm = true;
x.Open();
x.CreateSite(@"http://rad/sites/toto/",
                "Pas de Titre",
                "Pas de Description",
                1033,
                "STS#0",
                @"RM-ADFarmadmin",
                null,
                null,
                null,
                null);