Symfony2.1 display error: class_parents ()

I have a problem trying to get data from a table (via entity) using Doctrine2 in a Symfony2.1 project. Here is the controller where I get the error:

/**
 * Country list
 */
public function countrylistAction()
{
    $em = $this->getDoctrine()->getManager();
    $countryList = $em->getRepository('ProjectBaseBundle:SYS_TCountry')
        ->findAll();

    $serializer = new Serializer(array(new GetSetMethodNormalizer()),
        array('json' => new JsonEncoder()));

    return new Response($serializer->serialize($countryList, 'json'));
}

Essence:

<?php

namespace Company\Project\BaseBundle\Entity;

use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ORM\Entity
 * @ORM\Table(name="SYS_TCountry")
 */
class SYS_TCountry
{
    /**
     * @ORM\Id
     * @ORM\Column(type="string", length=3, nullable=false)
     * @var string
     */
    protected $idcountry;

    /**
     * @ORM\Column(type="string", length=75, nullable=false)
     * @Assert\NotBlank()
     * @var string
     */
    protected $name;

    ....

    public function getIdcountry()              { return $this->idcountry; }
    public function getName()                   { return $this->name; }
    public function getA2()                     { return $this->a2; }
    public function getA3()                     { return $this->a3; }
    public function getIdstatus()               { return $this->idstatus; }
    public function setIdcountry($idcountry)    { $this->idcountry = $idcountry; }
    public function setName($name)              { $this->name = $name; }
    public function setA2($a2)                  { $this->a2 = $a2; }
    public function setA3($a3)                  { $this->a3 = $a3; }
    public function setIdstatus($idstatus)      { $this->idstatus = $idstatus; }

    public function __toString()                { return $this->idcountry; }

}

config.yml:

# Doctrine Configuration
doctrine:
    dbal:
        driver:   %database_driver%
        host:     %database_host%
        port:     %database_port%
        dbname:   %database_name%
        user:     %database_user%
        password: %database_password%
        charset:  UTF8

    orm:
        auto_generate_proxy_classes: %kernel.debug%
        auto_mapping: true

And this is a mistake:

Warning: class_parents(): 
Class Company\Project\BaseBundle\Entity\SYS_TCountry does not exist and could not be loaded in 
/var/www/project/src/vendor/doctrine/common/lib/Doctrine/Common/Persistence/Mapping/RuntimeReflectionService.php line 40

This is strange because, as the Doctrine in the console says, the mapping is performed correctly: I am testing its execution php app / console doctrine: mapping: info:

[OK]   Company\Project\BaseBundle\Entity\SYS_TCountry

and if I execute the query in the console, everything will be fine -> app / console doctrine: query: sql 'SELECT * FROM SYS_TCountry', which return the results.

I don't know if Symfony2.1 is using . I need to configure something else for version 2.0, but it looks like mapping is the responsibility of Doctrine.