Transfering sessions across domains

Code:
function Security_BrowserInfo () {



        $this->load->library('user_agent');



        $data_browser['user_id']        = $this->Session_UserID();

        $data_browser['ip']             = $this->Custom_ReturnClientIP();



        $data_browser['agent_string']   = $this->agent->agent_string();

        $data_browser['version']        = $this->agent->version();

        $data_browser['platform']       = $this->agent->platform();

        $data_browser['is_browser']     = $this->agent->is_browser();

        //$data_browser['is_referral']    = $this->agent->is_referral();



        return $data_browser;

    }





    function Security_StoreBrowserInfo( $data_browser ) {



        $this->load->helper('date');

        $data_browser['datetime']       = mdate( "%Y-%m-%d %H:%i:%s" );



        $this->db->insert( 'c88v2_user_account_info_browser', $data_browser );

    

    }





    function Security_returnBrowserInfo( $user_id ) {



        $this->db->select('user_id, ip, agent_string, version, platform, is_browser, is_referral');

        $this->db->from('c88v2_user_account_info_browser');



        $this->db->where('user_id', $user_id );

        $this->db->order_by("datetime", "desc");



        $this->db->limit( 1 );



        $query = $this->db->get();





        $num_rows = $query->num_rows();



        if ( $num_rows <= 0)

        {

            die ('nothing returned');

        }

        else

        {

            $row = $query->row_array();



            $data_browser_db['user_id']        = $row['user_id'];

            $data_browser_db['ip']             = $row['ip'];



            $data_browser_db['agent_string']   = $row['agent_string'];

            $data_browser_db['version']        = $row['version'];

            $data_browser_db['platform']       = $row['platform'];

            $data_browser_db['is_browser']     = $row['is_browser'];

            //$data_browser_db['is_referral']    = $row['is_referral'];



            return $data_browser_db;

        }

    }







    function Security_CheckBrowserInfo ( $user_id ) {



        $data_browser_db = $this->Security_returnBrowserInfo( $user_id );



        $data_browser = $this->Security_BrowserInfo();



//            DEBUG

//            echo '<pre>';

//            print_r( $data_browser_db );

//            echo '</pre>';

//

//

//            echo '<pre>';

//            print_r( $data_browser );

//            echo '</pre>';



        $result = array_diff( $data_browser_db, $data_browser );



        if ( count( $result ) > 0 )

        {

            return FALSE;

        }

        else

        {

            return TRUE;

        }



    }





    

    function Security_Key_Regenerate( $user_id ) {



        $key_secret = md5( uniqid( rand( 100, 99999999 ), TRUE ) );

        $data_user['user_key_secret']   = $key_secret;



        $this->db->where( 'user_id', $user_id );

        $this->db->update( 'c88v2_user_account', $data_user );



    }