Problemas com inserção de dados usando Hibernate

Olá pessoal, a Paz a todos! Não estou conseguindo inserir dados na tabela usando o Hibernate. Uso um MacBook, Leopard 10.5.4, Intellij 8.0M1, Java 1.6.0, Hibernate 3.0 e PostgreSQL 8.3 com driver de conexão JDBC versão 3.0. Segue em anexo o Hibernate.cfg.xml, a classe Produto e AdicionaProduto. Abaixo segue o conteúdo do HibernateUtil e o Log de Saída.

package br.com.oxygen.hibernate;

import org.hibernate.SessionFactory;
import org.hibernate.Session;
import org.hibernate.cfg.AnnotationConfiguration;

/**
 * Created by IntelliJ IDEA.
 * User: thalesfernandosoarespinheirodasilva
 * Date: 19/09/2008
 * Time: 18:59:08
 * Obs: Classe responsável pelo gerenciamento das seasons (conexões com o Banco de Dados)
 */

public class HibernateUtil {
    //Global vars
    private static SessionFactory factory;  

    //Getters ans Setters


    //Default Constructor


    //Methods
    static {
        AnnotationConfiguration cfg = new AnnotationConfiguration();
        cfg.addAnnotatedClass(Produto.class);
        factory = cfg.buildSessionFactory();
    }

    public Session getSession() {
        return factory.openSession();
    }
}

Log:
/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/bin/java -Dfile.encoding=MacRoman -classpath /System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/deploy.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/dt.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/javaws.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/jce.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/management-agent.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/plugin.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/sa-jdi.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/charsets.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/classes.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/dt.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/jce.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/jconsole.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/jsse.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/laf.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/management-agent.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/…/Classes/ui.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/ext/apple_provider.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/ext/dnsns.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/ext/localedata.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/ext/sunjce_provider.jar:/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home/lib/ext/sunpkcs11.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/out/production/Hibernate:/Applications/Desenvolvimento/IntelliJ IDEA 8.0M1.app/lib/javaee.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/asm.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/hibernate-annotations.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/dom4j.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/postgresql-8.3-603.jdbc3.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/cglib.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/hibernate.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/log4j-1.2.15.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/jstl.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/commons-logging.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/standard.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/commons-collections.jar:/Users/thalesfernandosoarespinheirodasilva/IdeaProjects/Hibernate/lib/antlr.jar br.com.oxygen.hibernate.Exec

• Hibernate Annotations 3.2.1.GA
• Hibernate 3.2.6
• loaded properties from resource hibernate.properties: {hibernate.connection.autocommit=false, hibernate.connection.driver_class=org.postgresql.Driver, hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect, hibernate.format_sql=true, hibernate.connection.username=postgres, hibernate.connection.url=jdbc:postgresql://localhost/TesteJava, hibernate.bytecode.use_reflection_optimizer=false, hibernate.show_sql=true, hibernate.connection.password=****}
• Bytecode provider name : cglib
• using JDK 1.4 java.sql.Timestamp handling
• Binding entity from annotated class: br.com.oxygen.hibernate.Produto
• Bind entity br.com.oxygen.hibernate.Produto on table Produto
• Using Hibernate built-in connection pool (not for production use!)
• Hibernate connection pool size: 20
• autocommit mode: false
• using driver: org.postgresql.Driver at URL: jdbc:postgresql://localhost/TesteJava
• connection properties: {user=postgres, password=****, autocommit=false}
• RDBMS: PostgreSQL, version: 8.3.3
• JDBC driver: PostgreSQL Native Driver, version: PostgreSQL 8.3 JDBC3 with SSL (build 603)
• Using dialect: org.hibernate.dialect.PostgreSQLDialect
• Using default transaction strategy (direct JDBC transactions)
• No TransactionManagerLookup configured (in JTA environment, use of read-write or transactional second-level cache is not recommended)
• Automatic flush during beforeCompletion(): disabled
• Automatic session close at end of transaction: disabled
• JDBC batch size: 15
• JDBC batch updates for versioned data: disabled
• Scrollable result sets: enabled
• JDBC3 getGeneratedKeys(): disabled
• Connection release mode: auto
• Default batch fetch size: 1
• Generate SQL with comments: disabled
• Order SQL updates by primary key: disabled
• Order SQL inserts for batching: disabled
• Query translator: org.hibernate.hql.ast.ASTQueryTranslatorFactory
• Using ASTQueryTranslatorFactory
• Query language substitutions: {}
• JPA-QL strict compliance: disabled
• Second-level cache: enabled
• Query cache: disabled
• Cache provider: org.hibernate.cache.NoCacheProvider
• Optimize cache for minimal puts: disabled
• Structured second-level cache entries: disabled
• Echoing all SQL to stdout
• Statistics: disabled
• Deleted entity synthetic identifier rollback: disabled
• Default entity-mode: pojo
• Named query checking : enabled
• building session factory
• Not binding factory to JNDI, no JNDI name configured
  Hibernate:
  select
  nextval (‘hibernate_sequence’)
  Nome do Produto:Relógio
  Hibernate:
  insert
  into
  Produto
  (nome, validade, preco, id)
  values
  (?, ?, ?, ?)
  Hibernate:
  select
  nextval (‘hibernate_sequence’)
  Nome do Produto:Óculos
  Hibernate:
  insert
  into
  Produto
  (nome, validade, preco, id)
  values
  (?, ?, ?, ?)
  Hibernate:
  select
  nextval (‘hibernate_sequence’)
  Nome do Produto:Pen-Drive
  Hibernate:
  insert
  into
  Produto
  (nome, validade, preco, id)
  values
  (?, ?, ?, ?)

Process finished with exit code 0