title: Playframework: JPA error occurred (Unable to build EntityManagerFactory)
body: <p>I started to contribute to one Play project in Java, downloaded code, created Play project, added libraries and set all I could and then created database.
  Finally everything seemed to be ok, but when i run localhost:9000 i get this error:</p>
  
  <pre><code>JPA error
  @66kcmab39
  Internal Server Error (500) for request GET /favicon.ico
  
  JPA error
  A JPA error occurred (Unable to build EntityManagerFactory): Unable to get the default  Bean Validation factory
  play.exceptions.JPAException: Unable to build EntityManagerFactory
      at play.db.jpa.JPAPlugin.onApplicationStart(JPAPlugin.java:227)
      at play.Play.start(Play.java:427)
      at play.Play.detectChanges(Play.java:530)
      at play.Invoker$Invocation.init(Invoker.java:100)
      at Invocation.HTTP Request(Play!)
  Caused by: org.hibernate.HibernateException: Unable to get the default Bean Validation factory
  at org.hibernate.cfg.beanvalidation.BeanValidationActivator.applyDDL(BeanValidationActivator.java:104)
  at org.hibernate.cfg.AnnotationConfiguration.applyBeanValidationConstraintsOnDDL(AnnotationConfiguration.java:477)
  at org.hibernate.cfg.AnnotationConfiguration.applyConstraintsToDDL(AnnotationConfiguration.java:429)
  at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:403)
  at org.hibernate.cfg.Configuration.buildMappings(Configuration.java:1206)
  at org.hibernate.ejb.Ejb3Configuration.buildMappings(Ejb3Configuration.java:1459)
  at org.hibernate.ejb.EventListenerConfigurator.configure(EventListenerConfigurator.java:193)
  at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:1086)
  at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:890)
  at play.db.jpa.JPAPlugin.onApplicationStart(JPAPlugin.java:225)
  ... 4 more
  Caused by: java.lang.reflect.InvocationTargetException
  at org.hibernate.cfg.beanvalidation.BeanValidationActivator.applyDDL(BeanValidationActivator.java:95)
  ... 13 more
  Caused by: org.hibernate.HibernateException: Unable to build the default ValidatorFactory
  at org.hibernate.cfg.beanvalidation.TypeSafeActivator.getValidatorFactory(TypeSafeActivator.java:322)
  at org.hibernate.cfg.beanvalidation.TypeSafeActivator.applyDDL(TypeSafeActivator.java:83)
  ... 14 more
  Caused by: javax.validation.ValidationException: Unable to find a default provider
  at javax.validation.Validation$GenericBootstrapImpl.configure(Validation.java:264)
  at javax.validation.Validation.buildDefaultValidatorFactory(Validation.java:111)
  at org.hibernate.cfg.beanvalidation.TypeSafeActivator.getValidatorFactory(TypeSafeActivator.java:319)
  ... 15 more
  </code></pre>
  
  <p>Play version: 1.1.1<br>
  MySQL5<br>
  OS Ubuntu  </p>
  
  <p>Any idea what can be wrong?<br>
  Thanks<br>
  kvgr</p>