active record's transaction and Models

[eluser]akkumaru[/eluser]
it seems that i cannot use the database class’ transaction like this:

Code:

$this->load->model("model1","",TRUE);
$this->load->model("model2","",TRUE);

$this->db->trans_start();

$this->model1->update($value1);
$this->model2->update($value2);

$this->db->trans_complete();

first update will not be rolled back even when the second is failed..
how to solve this?

[eluser]akkumaru[/eluser]
can it be solved