Bill Stewart
This is exactly what I was addressing: remailers only have to get themselves certified as remailers and then prove their certification to the destination
You're both taking the wrong approach - make the originator of the message generate the hashcash, and make sure the remailer syntax lets them paste it in as needed. For chained remailers, generate multiple layers of hashcash. Maintaining whitelists is a losing game, but unnecessary here.
This works well enough. The more thorny problem to solve is that posed by Robert Costner: what do you do about nyms. You (the sender) can't include postage for nym reply blocks because you don't know (and mustn't know) the remailer chain pointed to by the reply block.
Mailing lists are still hard, and perhaps best handled by the user's software (or some fancy variant like user-selectable filters at the ISP mailbox.)
I think it's simplest to have the user explicitly allow the mailing
list.
You could possibly auto detect the pattern of a user subscribing to a
mailing list at the mail filter level also.
Adam
--
Now officially an EAR violation...
Have *you* exported RSA today? --> http://www.dcs.ex.ac.uk/~aba/rsa/
print pack"C*",split/\D+/,`echo "16iII*o\U@{$/=$z;[(pop,pop,unpack"H*",<>
)]}\EsMsKsN0[lN*1lK[d2%Sa2/d0