title: Class "Department" is mapped, but is not included in any persistence unit
body: <p>I am getting this error and I have no idea the reason: Class "Department" is mapped, but is not included in any persistence unit.</p>
  
  <p>I have two project.
  One is In my persistence.xml, between  tag, there is only two lines:</p>
  
  <pre><code>&lt;persistence-unit name="UserJPA"&gt;
  &lt;/persistence-unit&gt;
  </code></pre>
  
  <p>My class is:</p>
  
  <pre><code>package br.com.jm.user;
  import java.io.Serializable;
  import javax.persistence.Entity;
  import javax.persistence.Column;
  import javax.persistence.Id;
  import javax.persistence.Table;;
  
  @Entity
  @Table(name = "DEPARTMENT")
  public class Department implements Serializable {
  
      private static final long serialVersionUID = 1L;
  
      @Id
      private Long id;
      private String name;
  
  //getters and setters
  }
  </code></pre>
  
  <p>I am using EclipseLink2.1.2. Actually I can remove this if it makes the things easier.</p>
  
  <p>Hugs,
  Demetrio</p>