Change the date a cookie expires?

[nintendo]

How do I change the date a cookie is set to expire, to say April 15th??

PHP Code:

if ($vbulletin->userinfo['userid']) {
          if (!$_COOKIE['hacked']) {
              setcookie('hacked', '1', 1143964800);
          } elseif ($_COOKIE['hacked'] < 3) {
              setcookie('hacked', $_COOKIE['hacked'] + 1, 1143964800);
              echo 'Put whatever hacked HTML you want here';
              exit;
          }
      } 


Cookie is setup to expire on April 2, 2006 at 12:00 am.