Best way to handle passwords using CI library?

[eluser]xwero[/eluser]
i use following method to check if the login is valid

Code:

function valid_login($username,$password)
{
    $query = $this->db->select('password')->from('users')->where('username',$username)->get();
    if($query->num_rows() == 0)
    {
        return false;
    }
    else
    {
       $this->load->library('encrypt');
       foreach($query->result as $row)
       {
          if($this->encrypt->decode($password) == $row->password)
          {
             return true;
          }
       }
       return false;
    }
}

note : this works only in php5. for php4 you need to split the building of the query statement and use result_array in the loop.