Stop hotspot user from having to login all the time

I have three types of hotspot users: 1 day, 1 week, Unlimited.

The problem I am having is that everyday, or even multiple times a day, I have to log in to use the internet. I would like all or at least my unlimited users to only have to log in once. Or at least as long as a week or two. Any thoughts?

I think enabling cookie will help

If you use v6.x, you may try this http://wiki.mikrotik.com/wiki/Manual:Hotspot_Introduction#MAC_Cookie