We may need to consider some changes to the format of the information we add. The spec seems to indicate that the { and } characters are legal in an e-mail address, but I've rarely if ever seen them used. Maybe something like "{spam}original@address" instead of the comma-separator?

I would prefer to keep them separated, so that if you do reply, you just delete an invalid address, rather than have to modify one. (Or if you just send it anyway, at least the message gets through, as well as you getting a bounce).

It would obviously require people to modify their filter rules,

This would be ok with 1.1, but not with 1.0.1 (i.e. the 1.0_release_branch branch.

but it doesn't appear that rules for the current format would work correctly anyway.

Well, it works. It doesn't deal well with mail that also has "spam" in the To: header, but then notating the subject doesn't work with mail that has "spam," in the subject, either. It's more a limitation than a bug, IMO. I think that this won't be so important once there's a release that fixes the bug that stops people using a different trio of classification terms. Then people can just select something that they know they'll never see, and the rest of us with decent mailers can just get on with things as normal. (If we were to change anything, I would replace the comma with a space. Then people could change the classification names to "[spam]", "{spam}", "{[(jjuunnkk)]}" or whatever, as they pleased, and it would look relatively neat). =Tony Meyer