Symfony2 custom validator as a service not loaded

Question

Symfony2 custom validator as a service not loaded

EDIT: SOLVED

I am trying to create a special validator that works as a service (mainly to get entity manager).

I have been following the document and some blog posts, but cannot make it work. I am not getting an error, but the isValid method from my restriction is never called.

The My Entity class (which should be verified using "UniqueLem" (note that the Doctrine validator works):

namespace Elyotech\VersionManagerBundle\Entity;

use Gedmo\Mapping\Annotation as Gedmo;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;
use Me\AdminBundle\Validator\UniqueLem;
use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;

/**
 * @ORM\Entity(repositoryClass="Me\VersionManagerBundle\Repository\ProjectRepository")
 * @ORM\Table(name="project")
 * @UniqueLem
 * @UniqueEntity("name")
 */
class Project{...

My class of restrictions: namespace Elyotech \ AdminBundle \ Validator;

use Symfony \ Component \ Validator \ Constraint;

/*
 * @Annotation
 * */

class UniqueLem extends Constraint
{
    public $message = 'This value is already used';
    public $entity;
    public $property;

    public function validatedBy()
    {
        die; // Test to check if function is called
        return 'validator.unique';
    }

    public function getTargets()
    {
        return self::CLASS_CONSTRAINT;
    }

validator

    namespace Elyotech\AdminBundle\Validator;

use Doctrine\ORM\EntityManager;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;

class UniqueValidator extends ConstraintValidator
{
    private $entityManager;

    public function __construct( $entityManager)
    {
        $this->entityManager = $entityManager;
    }

    public function isValid($value, Constraint $constraint) {
        $this->setMessage($constraint->message);
        return false;
    }

Service Announcement:

 my.validator.unique:
   class:      %my.validator.unique.class%
   arguments: [@doctrine.orm.entity_manager]
   tags:
        - { name: validator.constraint_validator, alias: validator.unique }