title: javax.persistence.PersistenceException: org.hibernate.type.SerializationException: could not deserialize
body: <p>When executing a Criteria Query in hibernate, I get the following exception:</p>
  
  <pre><code>javax.persistence.PersistenceException: javax.persistence.PersistenceException: org.hibernate.type.SerializationException: could not deserialize: could not deserialize
  </code></pre>
  
  <p>What could be the problem?</p>
  
  <p>PS: although possibly not relevant, my hibernate version is hibernate-4.0.1 final.</p>