Trouble with importing annotations

I resolved this issue by adding the following to my entity file:

use Doctrine\ORM\Mapping as ORM;

So my file now looks like:

<?php

namespace Acme\CustomBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * Example
 *
 * @ORM\Entity
 * @ORM\Table(name="example")
 *
 */
class Example
{
    /**
     * @ORM\Column(type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     *
     * @var integer
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=125)
     *
     * @var string
     */
    private $title;

    /**
     * Get id
     *
     * @return integer
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Set title
     *
     * @param string $title
     *
     * @return Example
     */
    public function setTitle($title)
    {
        $this->title = $title;

        return $this;
    }

    /**
     * Get title
     *
     * @return string
     */
    public function gettitle()
    {
        return $this->title;
    }

}

I had a similar issue when using Silex, Doctrine2 and the Symfony-Validator.

The solution was to avoid using the SimpleAnnotationsReader and instead using the normal AnnotationReader (have a look at Doctrine\ORM\Configuration::newDefaultAnnotationDriver). You can then preface every entity with ORM\ (and of course inserting use Doctrine\ORM\Mapping as ORM; in every entity).