export ดาค้าเบจ เป้น excel ... ไฟล์ excel ที่ได้มันเป็นภาษาไทยอะครับ แก้ไงดี ขอบคุณครับ

 // Query Database
    $result=mysql_db_query($dbname,"select id,prename,name,sname,grade from appdata where course='$courseid' and sec='$section'")

    // Send Header
    header("Pragma: public");
    header("Expires: 0");
    header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
    header("Content-Type: application/force-download");
    header("Content-Type: application/octet-stream");
    header("Content-Type: application/download");;
    header("Content-Disposition: attachment;filename=$courseid-$sec.xls "); // แล้วนี่ก็ชื่อไฟล์
    header("Content-Transfer-Encoding: binary ");

    // XLS Data Cell

                xlsBOF();
                xlsWriteLabel(1,0,"Student Register $semester/$year");
                xlsWriteLabel(2,0,"COURSENO : ");
                xlsWriteLabel(2,1,"$courseid");
                xlsWriteLabel(3,0,"TITLE : ");
                xlsWriteLabel(3,1,"$title");
                xlsWriteLabel(4,0,"SETION : ");
                xlsWriteLabel(4,1,"$sec");
                xlsWriteLabel(6,0,"NO");
                xlsWriteLabel(6,1,"ID");
                xlsWriteLabel(6,2,"Gender");
                xlsWriteLabel(6,3,"Name");
                xlsWriteLabel(6,4,"Lastname");
                $xlsRow = 7;
                while(list($id,$prename,$name,$sname,$grade)=mysql_fetch_row($result)) {
                    ++$i;
                          xlsWriteNumber($xlsRow,0,"$i");
                          xlsWriteNumber($xlsRow,1,"$id");
                          xlsWriteLabel($xlsRow,2,"$prename");
                          xlsWriteLabel($xlsRow,3,"$name");
                          xlsWriteLabel($xlsRow,4,"$sname");
                    $xlsRow++;
                    }
                     xlsEOF();
                 exit();