setcookie很少时间在非Firefox中不起作用

Question

While testing some scripts, I've noticed, if expiration time is little (not zero) - cookie isn't available in Chrome, Opera, IE.

Example:

<?php
// setting cookie for 5 minutes
setcookie( 'cookie1' , 'Test', time()+60*5 );
echo $_COOKIE['cookie1'];
// yeap (it should display it only with refresh of page - I know:)
?>

In Firefox - I see the word Test (after opening and refreshing the page).

But in other browser - I don't see this. If I change time to time()+60*100 for example - it works fine in all browsers.

What's the reason of this?

UPD:

From Chome Dev Tool (sorry, don't know how Chrome firebug is called):

Date:Sun, 22 May 2011 10:29:59 GMT
Keep-Alive:timeout=15, max=99
Server:Apache/2.2.14 (Ubuntu)
Set-Cookie:Maslo123=Test; expires=Sun, 22-May-2011 10:34:59 GMT

Date is early than 'expires';

Answer 1

As we have already acquired that your server's time is wrong by few hours and thus the cookies are already expired.

The reason why Firefox still stores the cookie might be that it detect the odd time difference between the server and the client and uses the difference between the Date value and the Expires attribute value to determine the cookie expiration date.

These issues are also the reason why latter RFC standards like the current RFC 6265 prefer the relative time value of delta seconds.