Cookies

I use cookie to protect my web pages: setcookie("cookiename", "cookievalue", time()+1800); // set the expiry time to 30 minutes The time zone of my server is set to GMT+8. The server is running on a Redhat 7, apache and PHP 4 as a apache module. Now some users always get cookie expired error. I found that they are from different time zones, i.e. GMT+6, GMT+5. The users use IE to access my web pages. Could anyone tell me how to set the cookie independent of the time zone? Thanks! Au Chi Wa ERG HK ---------------------------- ERG Group -------------------------- The contents of this email and any attachments are confidential and may only be read by the intended recipient. -----------------------------------------------------------------