Hi, I'm having the same problem. I'm using jboss 4.2.2 and toplink. My persistence.xml is like this: <persistence.......> <persistence-unit name="xx"> oracle.toplink.essentials.PersistenceProvider .... </persistence-unit> When I start jboss, I get the following error: 15:00:05,453 INFO [STDOUT] [TopLink Warning]: 2009.06.01 03:00:05.453--java.lang.NullPointerException: null was thrown on attempt of PersistenceLoadProcessor to load class package.RegistroConsultarSolicitudesMigracionNumeracio nMovil. The class is ignored. Did you ever get the solution for this issue? Thanks in advance, Zaloa View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4234456#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...