title: NHibernate.QueryException with dynamic-component
body: <p>OK, this is going to be kind of a long shot, since it's a big system (which I don't claim to fully understand, yet), and the problem might not be with NHibernate itself, and I'm even having trouble reproducing it, but...</p>
  
  <p>I've got a class with a &lt;dynamic-component> section, and when I run a query on it (through my ASP.NET MVC app), it fails, but only sometimes.  (Yeah, the worst kind!)</p>
  
  <p>The exception I'm seeing is:</p>
  
  <pre><code>NHibernate.QueryException: could not resolve property:
  Attributes.MyAttributeName of: MyClassName
     at NHibernate.Persister.Entity.AbstractPropertyMapping.GetColumns(String propertyName)
     at NHibernate.Persister.Entity.AbstractPropertyMapping.ToColumns(String alias, String propertyName)
     at NHibernate.Persister.Entity.BasicEntityPropertyMapping.ToColumns(String alias, String propertyName)
     at NHibernate.Persister.Entity.AbstractEntityPersister.ToColumns(String alias, String propertyName)
     at NHibernate.Loader.Criteria.CriteriaQueryTranslator.GetColumns(String propertyName, ICriteria subcriteria)
     at NHibernate.Loader.Criteria.CriteriaQueryTranslator.GetColumnsUsingProjection(ICriteria subcriteria, String propertyName)
     at NHibernate.Criterion.CriterionUtil.GetColumnNamesUsingPropertyName(ICriteriaQuery criteriaQuery, ICriteria criteria, String propertyName, Object value, ICriterion critertion)
     at NHibernate.Criterion.CriterionUtil.GetColumnNamesForSimpleExpression(String propertyName, IProjection projection, ICriteriaQuery criteriaQuery, ICriteria criteria, IDictionary`2 enabledFilters, ICriterion criterion, Object value)
     at NHibernate.Criterion.SimpleExpression.ToSqlString(ICriteria criteria, ICriteriaQuery criteriaQuery, IDictionary`2 enabledFilters)
     at NHibernate.Loader.Criteria.CriteriaQueryTranslator.GetWhereCondition(IDictionary`2 enabledFilters)
     at NHibernate.Loader.Criteria.CriteriaJoinWalker..ctor(IOuterJoinLoadable persister, CriteriaQueryTranslator translator, ISessionFactoryImplementor factory, CriteriaImpl criteria, String rootEntityName, IDictionary`2 enabledFilters)
     at NHibernate.Loader.Criteria.CriteriaLoader..ctor(IOuterJoinLoadable persister, ISessionFactoryImplementor factory, CriteriaImpl rootCriteria, String rootEntityName, IDictionary`2 enabledFilters)
     at NHibernate.Impl.SessionImpl.List(CriteriaImpl criteria, IList results)
     at NHibernate.Impl.CriteriaImpl.List(IList results)
     at NHibernate.Impl.CriteriaImpl.UniqueResult[T]()
  ...my code below here...
  </code></pre>
  
  <p>Can anybody explain exactly what this QueryException means, i.e., so I can have an idea of what exactly it thinks is going wrong?</p>
  
  <p>Thanks!</p>