Thanks for the answer. Unfortunatly I have already tried this sort of manipuation on URLClassLoader instance, and I have had any sucess. In my last try, I had put the directory of the reports on the (dynamic) ckasspath, and I load the report with JRLoader.loadObjectFromLocation(...) I admit that the problems of class loader seem rather "magical". Can I use your wording for the text of the problem? Summary:No query executer factory registered error. Decription: JR should work as before and not rely on the fact that the JR classes/resources are present on the context classloader Best regards, Laurent Courtin