Comment 11 for bug 586908

It turns out that the cookie spec(s) (and browser implementations) don't allow setting a domain without a leading dot, so specifying a cookie with domain=launchpad.net isn't even possible. Even if it were, having the same cookie with two different domains (example.com and .example.com) wouldn't work because one will always override the other.

Despite the fact that Lynx is following the letter of the cookie spec(s) here in not forwarding cookies set on .launchpad.net during requests to launchpad.net, I filed a bug about the behavior (bug 675726).