Hibernate - Erro na inicializacao e Dois Bancos (Tomcat 5)

Configuration cfg = new Configuration();
    Configuration cfg2 = new Configuration();

    cfg.configure("/hibernate.cfg.xml");
    cfg2.configure("/hibernate2.cfg.xml");
      
    sessionFactory = cfg.buildSessionFactory();
    sessionFactory2 = cfg2.buildSessionFactory();

Estive lendo um tutorial sobre o Hibernate, e o autor utiliza um filter para resgatar a SessionFactory.
   :?: É realmente necessário utilizar um filter para gerenciar a SessionFactory?
  Por que a SessionFactory não pode ser chamada dentro do JavaBean. 
  Um abraço galera, segue abaixo o código utilizado no tutorial para resgatar a SessionFactory.  :wink:

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import net.sf.hibernate.SessionFactory;
import net.sf.hibernate.Session;
import net.sf.hibernate.Transaction;
import net.sf.hibernate.HibernateException;
import net.sf.hibernate.cfg.Configuration;

public class SessionManager implements Filter
{
	protected static ThreadLocal hibernateHolder = new ThreadLocal(); 
	protected static ThreadLocal txHolder = new ThreadLocal(); 
	protected static SessionFactory factory;
	
	public void init(FilterConfig filterConfig) throws ServletException
	{
		// Initialize hibernate
		try
		{
			factory = new Configuration().configure().buildSessionFactory();
		}
		catch (HibernateException ex) { throw new ServletException(ex); }
	}
	
	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) 
	throws IOException, ServletException
	{
		if (hibernateHolder.get() != null)
			throw new IllegalStateException(
					"A session is already associated with this thread!  "
					+ "Someone must have called getSession() outside of the context "
					+ "of a servlet request.");
		
		try {
			chain.doFilter(request, response);
		}
		finally {
			Session sess = (Session)hibernateHolder.get();
			Transaction tx = (Transaction)txHolder.get();
			if (sess != null) {
				hibernateHolder.set(null);
				
				try {
					if (tx != null) {
						tx.commit();
					}
					sess.close();
				}
				catch (HibernateException ex) { throw new ServletException(ex); }
			}
		}
	}
	
	public static Session getSession() throws HibernateException
	{
		Session sess = (Session)hibernateHolder.get();
		Transaction tx = (Transaction)txHolder.get();
		
		if (sess == null)
		{
			sess = factory.openSession();
			txHolder.set(sess.beginTransaction());
			hibernateHolder.set(sess);
		} else {
			if (tx == null) {
				throw new IllegalStateException("Transaction was allready rolled back");
			}
		}    
		return sess;
	}
	
	public static void rollback() throws HibernateException {
		Transaction tx = (Transaction)txHolder.get();
		if (tx == null) {
			throw new IllegalStateException("Transaction was allready rolled back");
		}
		
		tx.rollback();
		txHolder.set(null);
	}
	
	
	public void destroy() {
		try {
			factory.close();
		}
		catch (HibernateException ex) { throw new RuntimeException(ex); }
	}       
}

...
	protected static SessionFactory factoryPG;
	protected static SessionFactory factoryORCL;
	
	public void init(FilterConfig filterConfig) throws ServletException	{
		// Initialize hibernate
		try
		{
			Configuration pg = new Configuration().configure("hibernate.cfg.xml");
			Configuration orcl = new Configuration().configure("Oracle.cfg.xml");
			
			factoryPG = pg.buildSessionFactory();
			factoryORCL = orcl.buildSessionFactory();
		}
		catch (HibernateException ex) { throw new ServletException(ex); }
	}
...

...
	/**
	 * Resgata a session atual:
	 * 
	 * @param dataBase - 0: Postgresql, 1: Oracle
	 */
	public static Session getSession(int dataBase) throws HibernateException {
		Session sess = (Session) hibernateHolder.get();
		Transaction tx = (Transaction)txHolder.get();
		
		if (sess == null) {
			switch (dataBase) {
				case 0 : sess = factoryPG.openSession();
				case 1 : sess = factoryORCL.openSession();
			}
			txHolder.set(sess.beginTransaction());
			hibernateHolder.set(sess);
		} else {
			if (tx == null) {
				throw new IllegalStateException("Transaction was allready rolled back");
			}
		}    
		return sess;
	}
...