Why embedded OpenEJB fails to deploy my application?

I can't understand why an embedded OpenEJB container fails at the beginning with very un-informative message (sorry for a long log):

Running com.XXX.MyTest 
Apache OpenEJB 3.1.3    build: 20101015-05:42 
http://openejb.apache.org/
INFO - openejb.home = [skipped...] 
INFO - openejb.base = [skipped...] 
INFO - Configuring Service(id=Default Security Service, type=SecurityService, provider-id=Default Security Service)
INFO - Configuring Service(id=Default Transaction Manager, type=TransactionManager, provider-id=Default Transaction Manager) 
INFO - Found PersistenceModule in classpath: [skipped...]/target/classes 
INFO - Found EjbModule in classpath: [skipped...]/target/test-classes 
INFO - Beginning load: [skipped...]/target/classes 
INFO - AltDD persistence.xml -> file:[skipped...]/target/classes/META-INF/test.persistence.xml 
INFO - AltDD persistence.xml -> file:[skipped...]/target/classes/META-INF/test.persistence.xml 
INFO - Beginning load: [skipped...]/target/test-classes 
INFO - Configuring enterprise application: classpath.ear 
INFO - Configuring Service(id=Default Stateless Container, type=Container, provider-id=Default Stateless Container) 
INFO - Auto-creating a container for bean Finder: Container(type=STATELESS, id=Default Stateless Container) 
INFO - Configuring PersistenceUnit(name=wid, provider=org.hibernate.ejb.HibernatePersistence) 
INFO - Configuring Service(id=Default JDBC Database, type=Resource, provider-id=Default JDBC Database) 
INFO - Auto-creating a Resource with id 'Default JDBC Database' of type 'DataSource for 'abc'. 
INFO - Configuring Service(id=Default Unmanaged JDBC Database, type=Resource, provider-id=Default Unmanaged JDBC Database) 
INFO - Auto-creating a Resource with id 'Default Unmanaged JDBC Database' of type 'DataSource for 'abc'. 
INFO - Adjusting PersistenceUnit abc <jta-data-source> to Resource ID 'Default JDBC Database' from 'null' 
INFO - Adjusting PersistenceUnit abc <non-jta-data-source> to Resource ID 'Default Unmanaged JDBC Database' from 'null' 
INFO - Enterprise application "classpath.ear" loaded. 
INFO - Assembling app: classpath.ear 
Oct 28, 2010 2:00:20 PM org.hibernate.cfg.annotations.Version <clinit> 
INFO: Hibernate Annotations 3.5.6-Final 
Oct 28, 2010 2:00:20 PM org.hibernate.cfg.Environment <clinit> 
INFO: Hibernate 3.5.6-Final 
Oct 28, 2010 2:00:20 PM org.hibernate.cfg.Environment <clinit> 
INFO: hibernate.properties not found 
Oct 28, 2010 2:00:20 PM org.hibernate.cfg.Environment buildBytecodeProvider 
INFO: Bytecode provider name : javassist 
Oct 28, 2010 2:00:20 PM org.hibernate.cfg.Environment <clinit> 
INFO: using JDK 1.4 java.sql.Timestamp handling 
Oct 28, 2010 2:00:20 PM org.hibernate.annotations.common.Version <clinit> 
INFO: Hibernate Commons Annotations 3.2.0.Final 
Oct 28, 2010 2:00:20 PM org.hibernate.ejb.Version <clinit> 
INFO: Hibernate EntityManager 3.5.6-Final 
Oct 28, 2010 2:00:20 PM org.hibernate.ejb.Ejb3Configuration configure 
INFO: Processing PersistenceUnitInfo [ 
        name: abc 
        ...] 
INFO - PersistenceUnit(name=abc, provider=org.hibernate.ejb.HibernatePersistence) - provider time 328ms 
INFO - Undeploying app: classpath.ear 
ERROR - Application could not be deployed:  classpath.ear 
org.apache.openejb.OpenEJBException: Creating application failed: classpath.ear: org.apache.openejb.persistence.PersistenceUnitInfoImpl.getValidationMode()Ljavax/persistence/ValidationMode; 
        at org.apache.openejb.assembler.classic.Assembler.createApplication(Assembler.java:679) 
        at org.apache.openejb.assembler.classic.Assembler.createApplication(Assembler.java:450) 
        at org.apache.openejb.assembler.classic.Assembler.buildContainerSystem(Assembler.java:368) 
        at org.apache.openejb.assembler.classic.Assembler.build(Assembler.java:280) 
        at org.apache.openejb.OpenEJB$Instance.<init>(OpenEJB.java:125) 
        at org.apache.openejb.OpenEJB$Instance.<init>(OpenEJB.java:60) 
        at org.apache.openejb.OpenEJB.init(OpenEJB.java:271) 
        at org.apache.openejb.OpenEJB.init(OpenEJB.java:250)开发者_如何学C 
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
        [skipped...] 

Could you please help? Thanks.

That's because you're using JPA 2.0 which is AFAIK not yet supported by OpenEJB, see this thread and OPENEJB-1236. If you look closely at the Jira issue, it looks like this is fixed in the trunk. I just don't if the subtask is blocking or if it would work with a SNAPSHOT version of the trunk.