Oracle problem ugrading to phalcon 2.0

Hi all, I'm quite new to phalcon. I set up my very first project some days ago, today I've upgraded to phalcon 2.0 and my db access (Oracle!), has stopped working. This is the exeption I've got

$
PHP Fatal error:  Uncaught exception 'RuntimeException' with message 'Call to undefined method Phalcon\\Db\\Dialect\\Oracle::tableexists()' in /var/www/html/cupido/app/controllers/ApiController.php:49\nStack trace:\n#0 [internal function]: Phalcon\\Db\\Adapter->tableExists

and these are my snippets.

<?php
    //Setup the database service
    $di->set('db', function(){
        return new \Phalcon\Db\Adapter\Pdo\Oracle(array(
            "username" => "myuser",
            "password" => "mypwd",
            "dbname" => "(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=myhost)(PORT=1552)))(CONNECT_DATA=(SERVER = DEDICATED)(SID = MYSID)))"
        ));
    }); 

<?php
class Profiles extends \Phalcon\Mvc\Model
{
    public function initialize()
    {
        $this->setSource("PROFILES");
    }
}

<?php
    $profile = Profiles::findFirst(array(
        "conditions" => "USERID = ?1",
        "bind"       => array(1 => $dserid)
    ));

How can I fix them? Thank you very much! Stefano