Nope, not a browser/cookie issue. It has to do with http:// versus https://
katipo goes to https://www.photopost.com/members/members.pl (login_1) and then http://www.photopost.com/members/forum/index.php (login_2) and then
vB login to forums (login_3).
The admin panel links to the member area via https:// not http:// and the member area links to the forum via http:// not https:// so hence the three logins.