title: "could not instantiate" NHibernate.QueryException Raise By Combined Linq Query
body: <p>Executing the following NHibernate.Linq statement raises a <code>"could not instantiate: Reservation001.Services.ReservationDto"</code> NHibernate.QueryException containing an inner InvalidCast exception ("Object must implement IConvertible."):</p>
  
  <pre><code>var inOneStep = (from r in session.Linq&lt;Models.ReservationHeader&gt;()
      select new ReservationDto(r.Current));
  return inOneStep;
  </code></pre>
  
  <p>However, after splitting the above into two queries, with ToList() called on the results of the first, the code executes fine.</p>
  
  <pre><code>var step1 = (from r in session.Linq&lt;Models.ReservationHeader&gt;()
       select r).ToList();
  var step2 = from z in step1
       select new ReservationDto(z.Current);
  return step2;
  </code></pre>
  
  <p>Why does the single statement version raise an exception? </p>
  
  <p>Thank you,<br>
  Ben</p>