title: NHibernate - Conversion failed when converting datetime from binary/varbinary string
body: <p>Note, this is some ancient NHibernate installation! I have the following NHibernate class:</p>
  
  <pre><code>[Serializable]
  [Class(Table = "SomeEvents")]
  public class SomeEvent
  {
      [Property(Column="processDate")]
      public DateTime? ProcessDate { get; set; }
  }
  </code></pre>
  
  <p>When trying to update some events like:</p>
  
  <pre><code>using (ISession session = FDK_Hibernate_Manager.OpenSession())
  {
      IQuery query = session.CreateQuery(string.Format("FROM {0} e WHERE e.ContractId = :cid", typeof(ContractLeverconditiesEvent)));
      query.SetInt32("cid", contractId);
  
      foreach(var evnt in query.List().Cast&lt;SomeEvent&gt;())
      {
          evnt.ProcessDate = DateTime.Now;
          session.SaveOrUpdate(evnt);
      }
  
      session.Flush();
  }
  </code></pre>
  
  <p>I receive the following exception:</p>
  
  <blockquote>
    <p>Conversion failed when converting datetime from binary/varbinary string.</p>
  </blockquote>
  
  <p>So I basically guess that NHibernate doesn't understand my <code>DateTime?</code> yet. My NHibernate install doesn't have any fancy <code>Nullables.NHibernate.NullableDateTimeType</code>. So anyone has a clue to solve this ancient NHibernate issue?</p>