Generated SQL column names not correct

Hello,

I am trying to set up a many-to-many relationship for two models in my project. However, I get an error that the column userId does not exist. I have not told it to userId for the column name anywhere. If I paste the raw sql from mysql log into a database tool and change the column names, it works fine. Why is Phalcon using camelcase instead of underscore_case?

I have listed my three models with their defined relationships in initialize( ) below User Model

class User extends Model
{
public $id;
public $uuid;
public $signatureUuid;
public $firstName;
public $lastName;
public $loginEmail;
public $lastLogin;
public $accountStatus;
public $created;
public $modified;

public function columnMap()
{
    return array(
        'id'                => 'id',
        'uuid'              => 'uuid',
        'signature_uuid'    => 'signatureUuid',
        'login_email'       => 'loginEmail',
        'first_name'        => 'firstName',
        'last_name'         => 'lastName',
        'last_login'        => 'lastLogin',
        'account_status'    => 'accountStatus',
        'created'           => 'created',
        'modified'          => 'modified'
    );
}

/**
 * Initializes settings
 */
public function initialize()
{
    $this->hasManyToMany(
        'id',
        'Models\SaveForLaterItemModel',
        'user_id', 'item_id',
        'Models\ItemModel',
        'id',
        array('alias' => 'savedItems')
    );

    $this->skipAttributesOnUpdate(array(
        'id',
        'uuid',
        'created'
    ));
}
}

Item Model

class ItemModel extends Model
{
public $id;
public $uuid;
public $itemTypeId;
public $name;
public $description;
public $created;
public $modified;

public function columnMap()
{
    return array(
        'id'                        => 'id',
        'uuid'                      => 'uuid',
        'item_type_id'              => 'itemTypeId',
        'name'                      => 'name',
        'description'               => 'description',
        'created'                   => 'created',
        'modified'                  => 'modified'
    );
}

/**
 * Initializes settings
 */
public function initialize()
{
    $this->hasManyToMany(
        'id',
        'Models\SaveForLaterItemModel',
        'item_id', 'user_id',
        'Models\User',
        'id',
        array('alias' => 'users')
    );
}
}

Third model, linking the other two together

class SaveForLaterItemModel extends Model
{
public $item_id;
public $user_id;
public $created;
public $modified;

public function columnMap()
{
    return array(
        'item_id'                   => 'item_id',
        'user_id'                   => 'user_id',
        'created'                   => 'created',
        'modified'                  => 'modified'
    );
}
/**
 * Initializes settings
 */
public function initialize()
{
    $this->belongsTo('item_id', 'Models\ItemModel', 'id');
    $this->belongsTo('user_id', 'Models\User', 'id');

    $this->skipAttributesOnUpdate(array(
        'id',
        'created'
    ));
}
}

This is how I am using the relationship. I would like to find all items for a user:

$rows = User::findFirst()->getSavedItems();

Here is the resulting SQL from mysql.log:

40 Connect  [email protected] on foobar
40 Query    SELECT `users`.`id`, `users`.`uuid`, `users`.`signature_uuid`, `users`.`first_name`, `users`.`last_name`, `users`.`login_email`, `users`.`account_status`, `users`.`last_login`, `users`.`created`, `users`.`modified` FROM `users` LIMIT 1
40 Query    SELECT `items`.`id`, `items`.`uuid`, `items`.`item_type_id`, `items`.`name`, `items`.`description`, `items`.`created`, `items`.`modified` FROM `items` INNER JOIN `save_for_later_items` ON `save_for_later_items`.`itemId` = `items`.`id`  WHERE `save_for_later_items`.`userId` = '1'
40 Quit

Here is the error that I am receiving:

"Server Error","_Debug":"SQLSTATE[42S22]: Column not found: 1054 Unknown column 'save_for_later_items.userId' in 'where clause'"

If I change the column names itemId and userId to be item_id and user_id (like I would expect because a) that is how the column map is setup and b) that is how the table is defined), and run the query through a sql db tool, it works fine...

Why is Phalcon generating the incorrect column names?

Thank you