Hi, Trying to create a simple example from the bottom up, however I could not reproduce that either. However, removing all properties of the entities and adding them step by step up again, I'm now getting trouble to generate the sources again (same stacktrace as before) @Entity(value = "PERSON", noClassnameStored = true) public class Person implements org.apache.shindig.social.opensocial.model.Person { private static final long serialVersionUID = 1L; @Id private ObjectId objectId = null; private String id; .... // the next two methods are causing the trouble @Override public Map getAppData() { return personAppData; } @Override public void setAppData(Map appData) { Map m = new HashMap(); for (Iterator iterator = appData.keySet().iterator(); iterator .hasNext();) { String k = iterator.next(); String v = (String) appData.get(k); m.put(k, v); } personAppData = m; } Once these 2 methods are removed at least the source generation runs through, however there is now A Qstring class generated with compiler errors: public class QString extends BeanPath { ... public QString(BeanPath entity) { super(entity.getMetadata()); } public QString(PathMetadata metadata) { super(metadata); } ... } The compiler complains about : The constructor BeanPath(PathMetadata) is undefined. This is really out of my expertise now, so far what I got when using querydsl with JPA in that case was a StringPath. C. Thomas -----Original Message----- From: