title: GlassFish 3.1.1 - getting jdbc connection
body: <p>I'm trying to get OracleConnection from glassfish by this lines:</p>
  
  <pre><code>EntityManager em = getEntityManager();
  Connection c = em.unwrap(Connection.class);
  </code></pre>
  
  <p>But, in debugger I see that the actual class for c is ConnectionHolder40 class. Where I can find a jar with ConnectionHolder40 definition?</p>