I have a question about cookies,why is the time that the cookies expired not same as the time that parameter of session.cookie_lifetime set? for example, I wanna the cookies expired 5 minutes later,what should I do?I think I should set the parameter,as follow: session.cookie_lifetime = 300 right? But, after restart my apache server,I found the cookies maybe expired after 2 minutes,not 5 minutes as I want. why?