Fatal error: Call to a member function

i'm trying to unserialize Object. i run the documentaion sample.
code for classa.inc:

PHP Code:

---

<?php
class A {
     var $one = 1;
     function show_one() {
         echo $this->one;
     }

  }
?>

---

code for page1:

PHP Code:

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<?php
session_start();
include("classa.inc");
$a = new A;
$s = serialize($a);
setcookie("test",$s);
$nextPage = "page2.php";
header("Location: $nextPage");
?>

---

code for page2:

PHP Code:

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<?php
include("classa.inc");
$s =$_COOKIE["test"];
$a = unserialize($s);
if(is_object($a)){
    echo "a is an Object!<br/>"  ;
    $a->show_one();
}else{
    echo "a is not an Object!<br/>";
}
?>

---

Simple right.
result when run page1
a is not an Object!
i check and cookie test have been creted
i can't find why i cant use the object?
thanks for any help..

Don't you love magic quotes?

PHP Code:

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$s = stripslashes($_COOKIE["test"]); 


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