Lost session

[eluser]Unknown[/eluser]
please help me !!

My Session Data Not Set

codeigniter version: 2.0.0

in local no problem but in linux server PHP Version 5.2.17
my session data not set in IE and opera and safari Browser but Firefox is ok

in window server session set in IE and Firefox but linux not set

It is a bug?
I do not know

the classic session of php Good work
sample
session_start();
$_SESSION['username']="sara"

please help me!!!


this is sample code

sessiontest.php
location:
controller/sessiontest.php

Code:

class Sessiontest extends CI_Controller{
    function index(){
       $this->load->library('session');
       //$this->load->library('Native_session');
       $newdata = array(
                   'username'  => 'johndoe',
                   'email'     => '[email protected]',
                   'logged_in' => TRUE
               );

        $this->session->set_userdata($newdata);
        
        
            
    }
}

sessiontest2.php
location:
controller/sessiontest2.php

Code:

class sessiontest2 extends CI_Controller{
    function index(){
       $this->load->library('session');
       //$this->load->library('Native_session');        
       echo $this->session->userdata('username');
       echo $this->session->userdata('session_id');
      
    }
}