session problem

Hi all, I have 2 php page , whenever i click the submit in 1st page , the $_SESSION['LIST_OF_DATA'] display nothing in the 2nd page. If i do echo print_r($_SESSION['LIST_OF_DATA']) in first page , it displayed the data correctly. Anybody have any ideas why php session behaviour is like that ? Thanks - weetat below is the 1st page : <?php

       session_start();
       $arrayoffiles = listoffiles();

$params = array(

    		 'mode'      => 'Jumping',

'itemData' => $arrayoffiles, 'perPage' => 10,

       		 'delta' => 8,
        	 'append' => true,
    		 'clearIfVoid' => true,
    		 'useSessions' => true,
     		 'closeSession' => true,
       );

       $pager = & Pager::factory($params);
       $data  = $pager->getPageData();
       $links = $pager->getLinks();
       $_SESSION['LIST_OF_DATA'] = $data;

?> below is second page :

    <?php

        session_start();

        echo print_r($_SESSION['LIST_OF_DATA']);

    ?>