boolean in criteria query

My criteria looks like:

Session.CreateCriteria(typeof(User))
  .Add(Expression.Eq("IsActive", 1);

Do I put 1 or True for the IsActive boolean check? (non seem to work?)

what are my options?

How is your DB defined?

I use this code: customer.Add(new EqExpression("Deleted", false)); To access a field in my database where the "Deleted" field is defined as a bit that does not allow null. (This is a SQL 2005 DB)