after using the cross-login here in bugzilla the cookies are left in a state that makes it
impossible to log into yabb on the following days (if you haven't logged out there).

i can think of two possible reasons:
- bad domain ".processing.org" instead of "processing.org"
- users internet connection ip address has changed from on day to the other

the only way to log-in to yabb on the following day is to remove the cookies by hand.

the problem was that YaBB does not set a domain when writing the cookie. the cookie was
automatically linked to the domain "processing.org" (from where it came) but not
".processing.org" (starting with a dot). this caused YaBB to read the second cookie after it's
own and therefore to not be able to logout or relogin.

the problem is now resolved by altering cookie() inside Subs.pl to add the domain
processing.org to the cookie.