Mine

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">
    <persistence-unit name="PrototypePU" transaction-type="JTA">
        <jta-data-source>jdbc/PrototypeDS</jta-data-source>
        <properties>
            <property name="toplink.logging.level" value="FINE" />
            <property name="toplink.target-database" value="MySQL4" />
            <property name="toplink.ddl-generation" value="none" />
            <property name="toplink.descriptor.customizer.BaseEntity" value="com.rampgroup.jpa.audit.AuditHandler" />
        </properties>
    </persistence-unit>
</persistence>