I found the solution, but I don't know how to translate those solution (in NHibernate) to ActiveRecord.
Instead of using a named queries (which I'm not even sure if Castle supports) you could create a native query which is essentially the same thing IMO.
public static DateTime FindServerDateTime()
{
return Helper.GetSession()
.CreateSQLQuery("select getdate()")
.UniqueResult<DateTime>();
}
Replace Helper.GetSession()
with whatever function or property you use to fetch the Castle AR session.