Using SQL Server 2008 Geography types with nHibernate's CreateSQLQuery

sqlstring = string.Format("set nocount on;update myusers set geo=geography::Point({0}, {1}, 4326) where userid={2};", mlat, mlong, userid);
_session.CreateSQLQuery(sqlstring).ExecuteUpdate();

set nocount on;update myusers set geo=geography@p0({0}, {1}, 4326) where userid={2};