GlassFish não esta Injetando o EntityManager na minha classe DAO

package key.dao;

import bean.Licensa;
import javax.annotation.Resource;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import javax.transaction.UserTransaction;

/**
 *
 * @author ekszuki
 */
public class LicensaDAO {

   @PersistenceContext(name = "keyglobalpecPU")
   private EntityManager em;

  @Resource  
  private UserTransaction utx; 

   public EntityManager getEntityManager() {
      return em ;
   }

   public Licensa getLicensaByLicenseKey(String licenseKey) {
      Query query = em.createNamedQuery("Licensa.findByLicensekey");
      query.setParameter("licensekey", licenseKey);
      return (Licensa) query.getSingleResult();
   }
}

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package key.managedbean;

import bean.Liberacao;
import bean.Licensa;
import br.com.sygnux.util.Util;
import java.text.DateFormat;
import java.text.ParseException;
import java.util.Calendar;
import java.util.Date;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.Resource;
import javax.faces.application.FacesMessage;
import javax.faces.context.FacesContext;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import javax.transaction.UserTransaction;
import key.Cript.Criptografia;
import key.dao.LicensaDAO;

/**
 *
 * @author Ekszuki
 */
public class MyKeyManagerBean {

   private String theOldKey;
   private String theNewKey;
   private int Dias;

   @PersistenceContext(name = "keyglobalpecPU" )
   private EntityManager em;

   @Resource
   private UserTransaction utx;

   private FacesContext context ;
   // private LicensaJpaController licensaController ;

   public MyKeyManagerBean() {
      context = FacesContext.getCurrentInstance() ;
   }

   public String getTheNewKey() {
      return theNewKey;
   }

   public String getTheOldKey() {
      return theOldKey;
   }

   public void setTheOldKey(String theOldKey) {
      this.theOldKey = theOldKey;
   }

   public int getDias() {
      return Dias;
   }

   public void setDias(int Dias) {
      this.Dias = Dias;
   }
   /** Creates a new instance of MyKeyManagerBean */
   public String renovarChave() {
      Criptografia crip = new Criptografia();
      DateFormat df = DateFormat.getDateInstance();
      Licensa licensa = null;
      Query query = null;

      try {

         // verifica se esta liberado para gerar chaves
         utx.begin() ;
         query = em.createNamedQuery("Liberacao.findAll");
         Liberacao liberacao = (Liberacao) query.getSingleResult();

         if (liberacao.getStatus().equals("N")) {
           throw new Throwable("O Sistema está bloqueado para atualizar as chaves");
         }

         // find old key in database
         query = em.createNamedQuery("Licensa.findByLicensekey");
         query.setParameter("licensekey", theOldKey);
         licensa = (Licensa) query.getSingleResult();

         // verifica se a licensa informada esta cancelada
         if (licensa.getStatus().equals("R") ) {
            throw new Throwable("Licensa informada ja foi renovada");
         }

         Date hoje = new Date();

         // verifica se a chave esta vencida
         int diasParaTravar = Util.dataDiff(hoje, licensa.getDataTrava());

         // Permiti gerar a nova chave a partir de 10 dias para vencer 
         if (diasParaTravar > 10) {
            throw new Throwable("Chave esta dentro do periodo de validade");
         }
         String key = crip.Desencripta(theOldKey);

         String hd = key.substring(10, 18);
         Date data = df.parse(key.substring(0, 10));

         Calendar dataProximaTrava = Calendar.getInstance();
         dataProximaTrava.setTime(data);
         dataProximaTrava.add(Calendar.DATE, Dias);

         theNewKey = crip.Encripta(df.format(dataProximaTrava.getTime()) + hd);

         // passa a licensa informada para cancelada
         licensa.setStatus("R") ;

         em.persist(licensa) ;

         //licensaController.edit(licensa) ;

         // registra nova licensa e seus dados
         Licensa novaLicensa = new Licensa() ;
         novaLicensa.setDataGeracao(hoje);
         novaLicensa.setDataTrava(dataProximaTrava.getTime());
         novaLicensa.setHdkey(hd);
         novaLicensa.setLicensekey(theNewKey) ;
         novaLicensa.setCliente( licensa.getCliente() ) ;
         novaLicensa.setStatus("A") ;

         em.persist(novaLicensa);

         utx.commit();

      } catch (ParseException ex) {
         Logger.getLogger(MyKeyManagerBean.class.getName()).log(Level.SEVERE, null, ex);
      } catch ( Throwable ex ) {
         FacesContext.getCurrentInstance().addMessage("invalido", new FacesMessage(FacesMessage.SEVERITY_ERROR, ex.getMessage(), "Detail") );
      }
      return "refresh";
   }


   public String teste() {

      Licensa lic ;
      LicensaDAO DAO = new LicensaDAO() ;

      try {
         lic = DAO.getLicensaByLicenseKey( theOldKey ) ;

         System.out.println("Vindos do DAO: " + lic.getLicensekey() ) ;

      } catch( Exception e ) {
         e.printStackTrace();
      }



      return "refresh" ;
   }

}