For most of the evening (1900 to 2330 UK), each time I tried to get to the Forum page with Safari, it came up with a 400 Bad Request page. The jist of the error seemed to be that the cookie string was too long. After getting to the forums fine with Firefox, I quit Safari (which had probably been open for two or three weeks) and emptied its cache. And then the forums came back properly with me logged in and my last visit at 6pm UK time which was correct. Any idea why this might have happened?