title: datanucleus run JDO webapp in Jboss
body: <p>I'm getting no where trying to figure how to run a simple test on Jboss using mongodb...
  I followed this tutorial:
  <a href="https://developer.jboss.org/wiki/GettingStartedWithJDOOnJbossAS7InSevenSteps" rel="nofollow">https://developer.jboss.org/wiki/GettingStartedWithJDOOnJbossAS7InSevenSteps</a>
  But this example uses a SQL (oracle) not mongodb, so I tried to figure out a way to do it, but nothing...
  Can someone help me out on how to install datanucleus on Jboss or tomcat, if it's easier, using mongodb?</p>
  
  <p>I get this error from jboss regarding the PU:</p>
  
  <pre><code>jboss.persistenceunit."DN.war#Profiles":
  javax.persistence.PersistenceException: [PersistenceUnit: Profiles] 
  Unable to build EntityManagerFactory
  ...Caused by: javax.persistence.PersistenceException: [PersistenceUnit: Profiles] Unable to build EntityManagerFactory
  at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:924)
  at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:899)
  ...Caused by: org.hibernate.HibernateException: Connection cannot be null when 'hibernate.dialect' not set
  </code></pre>
  
  <p>It seems it assumes this is a hibernate project... </p>
  
  <p>If someone could help me out on how to setup a persistence.xml to use mongodb on a webserver, I would be very appreciative.</p>
  
  <p>Thank you very much in advance.  </p>