Persistence.xml - JET with JPA question in How Do I? Posted October 4, 2010 · Report reply Please send an example to reproduce the problem to Support Dept. (java at excelsior-usa.com). Also send your JET project files (*.prj, *.jpn) and the Java command line that you use to start your application on the standard JRE. We will check if the settings are correct. We will examine the problem on our end and post a follow-up with the results in this topic.