it's a cookie problem but try,
in internet explorer:
Tools> Internet options> security>
under "select a zone to select or change security settings"
there should be a big green tick "trusted sites"...click it
then click the "sites" button (previously grayed out until the above step)...
then click "add" to add this site ..the details should be filled in for you if you're on the forum when you do the above...if not fill it in with http//:
www.britishbadgeforum.com