Description:
------------
Hello

I have un bug with the function serialize.
I need to serialize object for testing if they not changed.
The bug appear when i serialize type is double but disappear when i unzerialize.
i explain this in the reproduce code.
i think it's a problem of approximation.

thank for the answer.

ps: my english is not very good, excuse me

Reproduce code:
---------------
<?php

$test = 13.1;
echo "test = ".$test."<br>";
$test2 = serialize($test);
echo "test2(serialize) = ".$test2."<br>";
echo "test2(unserialize) = ".unserialize($test2);

?>

Expected result:
----------------
test = 13.1
test2(serialize) = d:13.1;
test2(unserialize) = 13.1

Actual result:
--------------
test = 13.1
test2(serialize) = d:13.0999999999999996447286321199499070644378662109375;
test2(unserialize) = 13.1