How to avoid the string conversion

[eluser]ReyPM[/eluser]
Hi, I've this code:

Code:

public function get_received() {
    $this->db
            ->select('p.*, rcp.*, msg.*')
            ->distinct()
            ->join($this->db->dbprefix('recipient') . ' rcp', 'rcp.user_id = ' . (int) $this->current_user->id)
            ->join($this->db->dbprefix('profiles') . ' p', 'p.user_id = ' . (int) $this->current_user->id)
            ->join($this->db->dbprefix('messages') . ' msg', 'msg.id = rcp.message_id')
            ->order_by('msg.date');

    return $this->db->get($this->db->dbprefix('messages'))->result();
  }

But this cause this error:

A Database Error Occurred
Error Number: 1054
Unknown column '1' in 'on clause'
SELECT DISTINCT `p`.*, `rcp`.*, `msg`.* FROM (`default_messages`) JOIN `default_recipient` rcp ON `rcp`.`user_id` = `1` JOIN `default_profiles` p ON `p`.`user_id` = `1` JOIN `default_messages` msg ON `msg`.`id` = `rcp`.`message_id` ORDER BY `msg`.`date`

Filename: /var/www/html/cmv/addons/default/modules/messages/models/messages_m.php
Line Number: 31

Because automatically convert the 1 to '1' meaning convert from INT to STRING and I don't want that, how to avoid this behaviour?
Cheers