DateTime::CreateFromFormat para PHP 5.2.14

Podría extender la clase DateTime e implementar createFromFormat() tú mismo así:-

class MyDateTime extends DateTime
{
    public static function createFromFormat($format, $time, $timezone = null)
    {
        if(!$timezone) $timezone = new DateTimeZone(date_default_timezone_get());
        $version = explode('.', phpversion());
        if(((int)$version[0] >= 5 && (int)$version[1] >= 2 && (int)$version[2] > 17)){
            return parent::createFromFormat($format, $time, $timezone);
        }
        return new DateTime(date($format, strtotime($time)), $timezone);
    }
}

$dateTime = MyDateTime::createFromFormat('Y-m-d', '2013-6-13');
var_dump($dateTime);
var_dump($dateTime->format('Y-m-d'));

Esto funcionará en todas las versiones de PHP>=5.2.0.

Vea aquí una demostración http://3v4l.org/djucq