Thanks for your answer!
"First thing to notice is that if you are using 2 different persistence units, then you can clean up 'org.jbpm.persistence.jpa' by removing all the 'org.jbpm.task.*' classes." =>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<persistence version="1.0"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd
http://java.sun.com/xml/ns/persistence/orm
http://java.sun.com/xml/ns/persistence/orm_1_0.xsd"
xmlns:orm="http://java.sun.com/xml/ns/persistence/orm"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/persistence">
<persistence-unit name="org.jbpm.persistence.jpa">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:/jdbc/jbpm-ds</jta-data-source>
<mapping-file>META-INF/JBPMorm.xml</mapping-file>
<mapping-file>META-INF/Taskorm.xml</mapping-file>
<mapping-file>META-INF/ProcessInstanceInfo.hbm.xml</mapping-file>
<class>org.jbpm.persistence.processinstance.ProcessInstanceInfo</class>
<class>org.drools.persistence.info.SessionInfo</class>
<class>org.drools.persistence.info.WorkItemInfo</class>
<class>org.jbpm.process.audit.ProcessInstanceLog</class>
<class>org.jbpm.process.audit.NodeInstanceLog</class>
<class>org.jbpm.process.audit.VariableInstanceLog</class>
<properties>
<property name="hibernate.max_fetch_depth" value="3"/>
<property name="hibernate.hbm2ddl.auto" value="update" />
<property name="hibernate.show_sql" value="false" />
<property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.BTMTransactionManagerLookup" />
<!--
<property name="hibernate.transaction.manager_lookup_class" value="org.jbpm.integration.console.JBPMTransactionManager" />
-->
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
</properties>
</persistence-unit>
<persistence-unit name="org.jbpm.task">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:/jdbc/jbpm-ds</jta-data-source>
<mapping-file>META-INF/Taskorm.xml</mapping-file>
<class>org.jbpm.task.Attachment</class>
<class>org.jbpm.task.Content</class>
<class>org.jbpm.task.BooleanExpression</class>
<class>org.jbpm.task.Comment</class>
<class>org.jbpm.task.Deadline</class>
<class>org.jbpm.task.Comment</class>
<class>org.jbpm.task.Deadline</class>
<class>org.jbpm.task.Delegation</class>
<class>org.jbpm.task.Escalation</class>
<class>org.jbpm.task.Group</class>
<class>org.jbpm.task.I18NText</class>
<class>org.jbpm.task.Notification</class>
<class>org.jbpm.task.EmailNotification</class>
<class>org.jbpm.task.EmailNotificationHeader</class>
<class>org.jbpm.task.PeopleAssignments</class>
<class>org.jbpm.task.Reassignment</class>
<class>org.jbpm.task.Status</class>
<class>org.jbpm.task.Task</class>
<class>org.jbpm.task.TaskData</class>
<class>org.jbpm.task.SubTasksStrategy</class>
<class>org.jbpm.task.OnParentAbortAllSubTasksEndStrategy</class>
<class>org.jbpm.task.OnAllSubTasksEndParentEndStrategy</class>
<class>org.jbpm.task.User</class>
<properties>
<property name="hibernate.max_fetch_depth" value="3"/>
<property name="hibernate.hbm2ddl.auto" value="update" />
<property name="hibernate.show_sql" value="false" />
<!--
<property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.BTMTransactionManagerLookup" />
-->
<property name="hibernate.transaction.manager_lookup_class" value="org.jbpm.integration.console.JBPMTransactionManager" />
</properties>
</persistence-unit>
</persistence>
wheere should I put dependencies?
Laura