src/ResetableEntityManager.php
public function copy($entity, $deep = false)
    {
        try{
            return $this->entityManager->copy($entity, $deep);
        } catch(ORMException $e) {
            if (!$this->entityManager->isOpen()) {
                $this->resetEntityManager();
            }
            throw $e;
        }
    }
public function copy($entity, $deep = false)
    {
        try{
            return $this->entityManager->copy($entity, $deep);
        } catch(ORMException $e) {
            if (!$this->entityManager->isOpen()) {
                $this->resetEntityManager();
            }
            throw $e;
        }
    }
{@inheritDoc}

@todo Implementation need. This is necessary since $e2 = clone $e1; throws an E_FATAL when access anything on $e:
Fatal error: Maximum function nesting level of '100' reached, aborting!