ion auth, users does not have any password

I'm new to Ion auth, so I've followed some tutorials to start. I can log with the default admin account, and then create other users.

The problem is that other users cannot connect. And when I check directly in the database, the default user has an usual string of ununderstandable characters in the password case and the salt case is empty. But my other users have 0 in the password case and the salt case contain NULL.

So I think that there is a problem in one of the sign up fonctions or in the config.

Does it ring a bell to anyone?

Here is the default user_create fonction:

function create_user()
{
    $this->data['title'] = "Create User";

    if (!$this->ion_auth->logged_in() || !$this->ion_auth->is_admin())
    {
        redirect('auth', 'refresh');
    }

    $tables = $this->config->item('tables','ion_auth');

    //validate form input
    $this->form_validation->set_rules('first_name', $this->lang->line('create_user_validation_fname_label'), 'required|xss_clean');
    $this->form_validation->set_rules('last_name', $this->lang->line('create_user_validation_lname_label'), 'required|xss_clean');
    $this->form_validation->set_rules('email', $this->lang->line('create_user_validation_email_label'), 'required|valid_email|is_unique['.$tables['users'].'.email]');
    $this->form_validation->set_rules('phone', $this->lang->line('create_user_validation_phone_label'), 'required|xss_clean');
    $this->form_validation->set_rules('company', $this->lang->line('create_user_validation_company_label'), 'required|xss_clean');
    $this->form_validation->set_rules('password', $this->lang->line('create_user_validation_password_label'), 'required|min_length[' . $this->config->item('min_password_length', 'ion_auth') . ']|max_length[' . $this->config->item('max_password_length', 'ion_auth') . ']|matches[password_confirm]');
    $this->form_validation->set_rules('password_confirm', $this->lang->line('create_user_validation_password_confirm_label'), 'required');

    if ($this->form_validation->run() == true)
    {
        $username = strtolower($this->input->post('first_name')) . ' ' . strtolower($this->input->post('last_name'));
        $email    = strtolower($this->input->post('email'));
        $password = $this->input->post('password');

        $additional_data = array(
            'first_name' => $this->input->post('first_name'),
            'last_name'  => $this->input->post('last_name'),
            'company'    => $this->input->post('company'),
            'phone'      => $this->input->post('phone'),
        );
    }
    if ($this->form_validation->run() == true && $this->ion_auth->register($username, $password, $email, $additional_data))
    {
        //check to see if we are creating the user
        //redirect them back to the admin page
        $this->session->set_flashdata('message', $this->ion_auth->messages());
        redirect("auth", 'refresh');
    }
    else
    {
        //display the create user form
        //set the flash data error message if there is one
        $this->data['message'] = (validation_errors() ? validation_errors() : ($this->ion_auth->errors() ? $this->ion_auth->errors() : $this->session->flashdata('message')));

        $this->data['first_name'] = array(
            'name'  => 'first_name',
            'id'    => 'first_name',
            'type'  => 'text',
            'value' => $this->form_validation->set_value('first_name'),
        );
        $this->data['last_name'] = array(
            'name'  => 'last_name',
            'id'    => 'last_name',
            'type'  => 'text',
            'value' => $this->form_validation->set_value('last_name'),
        );
        $this->data['email'] = array(
            'name'  => 'email',
            'id'    => 'email',
            'type'  => 'text',
            'value' => $this->form_validation->set_value('email'),
        );
        $this->data['company'] = array(
            'name'  => 'company',
            'id'    => 'company',
            'type'  => 'text',
            'value' => $this->form_validation->set_value('company'),
        );
        $this->data['phone'] = array(
            'name'  => 'phone',
            'id'    => 'phone',
            'type'  => 'text',
            'value' => $this->form_validation->set_value('phone'),
        );
        $this->data['password'] = array(
            'name'  => 'password',
            'id'    => 'password',
            'type'  => 'password',
            'value' => $this->form_validation->set_value('password'),
        );
        $this->data['password_confirm'] = array(
            'name'  => 'password_confirm',
            'id'    => 'password_confirm',
            'type'  => 'password',
            'value' => $this->form_validation->set_value('password_confirm'),
        );

        $this->_render_page('auth/create_user', $this->data);
    }
}

This means your server doesn't support bcrypt. You should upgrade you're PHP version to >= 5.3.7.

If thats not a possibility you can change the hashing algo to SHA1 in the Ion Auth config file.