Description:
------------
apache.exe application error
 "0x0076cc6a" instruction referenced memory "0x45532730"
 can not be readed.


Reproduce code:
---------------
<?
ob_start();
$dsn = 'sqlite:view.db';
try {
    $dbh = new PDO($dsn, $user, $password);
    $dbh->beginTransaction();
    $sqlno = 'SELECT max(serial) FROM picture';
    $sthno = $dbh->prepare($sqlno);
    $sthno->execute();
    $res = $sthno->fetch();
    $maxnum = $res[0];
} catch (PDOException $e) {
   echo 'Connection failed: ' . $e->getMessage();
}

if (!$num)
{
$num = 1;
try {
    $dbh = new PDO($dsn, $user, $password);
    $dbh->beginTransaction();
    $sql = 'SELECT length,code FROM picture where serial ='.$num;
    $sth = $dbh->prepare($sql);
    $sth->execute();
    $result = $sth->fetch();
    $dsn=null;
} catch (PDOException $e) {
   echo 'Connection failed: ' . $e->getMessage();
   $dsn=null;
}
header("Content-type: image/jpeg");
header("Refresh:2;URL=autoshow.php");
echo base64_decode($result[1]);
setcookie("num",$num+1);
}
elseif($num <= $maxnum)
{
	$num=$_COOKIE["num"];
try {
    $dbh = new PDO($dsn, $user, $password);
    $dbh->beginTransaction();
    $sql = 'SELECT length,code FROM picture where serial ='.$num;
    $sth = $dbh->prepare($sql);
    $sth->execute();
    $result = $sth->fetch();
    $dsn=null;
} catch (PDOException $e) {
   echo 'Connection failed: ' . $e->getMessage();
   $dsn=null;
}
header("Content-type: image/jpeg");
header("Refresh:2;URL=autoshow.php");
echo base64_decode($result[1]);
setcookie("num",$num+1);
}
else
{
 print "<script language=\"javascript\">";
 print "alert (\"ȫ??ͼƬ??ʾ????\");";
 print "window.close();";
 print "</script>"; 
}
?>

Expected result:
----------------
the page refreshed every 2 second to show anther picture

Actual result:
--------------
just show the first picture then it core down.