title: Working Maven3 configuration for AppEngine + DataNucleus + JPA 2
body: <p>I'm trying to create GAE project via Maven and I'm facing problem with persistence libraries configuration. I try including different dependencies and specifying different scopes, but I always get some errors like:</p>
  
  <pre><code>java.lang.NoClassDefFoundError: org/datanucleus/ObjectManagerFactoryImpl
  </code></pre>
  
  <p>.</p>
  
  <pre><code>java.lang.NoClassDefFoundError: javax/persistence/spi/ProviderUtil
  </code></pre>
  
  <p>.</p>
  
  <pre><code>java.lang.NoClassDefFoundError: org/datanucleus/ClassLoaderResolver
  </code></pre>
  
  <p>.</p>
  
  <pre><code>Invocation of init method failed; nested exception is javax.persistence.PersistenceException: No persistence providers available for "transactions-optional" after trying the following discovered implementations: org.datanucleus.api.jpa.PersistenceProviderImpl
  </code></pre>