The remember me options should only work when the cookies are set. If you need to manually delete your cookies in IE8 you can do that by going to Tools > Delete Browsing History. In here make sure that you only check the box for cookies then click on the delete button. There are ways to delete specific cookies also, I found this entry when searching for this:
I replied to your ticket with some more info. Please login and visit your support history to update the ticket. If you have any further questions please post them to the ticket so that we can keep it all in one place.