Description:
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When using a PDO connection object unserialize from a serialized string, PHP crashed. Error message: "Application Failure  Apache.exe 2.0.54.0 in php5ts.dll 5.1.0.0 at offset 0012bb10".

Is it really a bug? My PHP version is 5.1.0RC1.

Reproduce code:
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<?php
$connection = new PDO("mysql:dbname=test;host=localhost", "root", "root");
$connection = unserialize(serialize($connection));
$stmt = $connection->query("SELECT * FROM users");
$connection = null;
?>

Expected result:
----------------
The code worked well

Actual result:
--------------
The browser said "can not find server" and PHP crashed with message "Application Failure  Apache.exe 2.0.54.0 in php5ts.dll 5.1.0.0 at offset 0012bb10".