JPOX 1.1.3, an open source implementation of Java Data Objects (JDO) 2.0, has been released. that provides transparent persistence to Java objects. It supports most major SQL databases and can be queried using either JDOQL or SQL. 1.1.3 simplifies user-defined type mappings and supports same-named subclass fields in the superclass table. It's published under the Apache 2.0 License.