I dislike the idea of whitelists. Here is a possible compromise solution that could be added to Mailwasher

Every email to the email address "person@email.address" received is automatically bounced with an added message "As an anti spam measure from an unknown address, if you wish this email to be read, please resend it to this email address: "person.5T6y62@email.address" - note the extra suffix.
(This email address has to be drawn in graphics to defeat robots and added to the message as an attachment).

This suffix is randomly generated for every account that the mailwasher user has and can be regenerated at any time by the user., if spam gets through.

So people can still publish their email address "person@emailaddress" etc and spammers will need to manually reply to get an email address.

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Obviously it woudl be real pain for systems like hotmail where there is no wildcard email address, but instead the suffix phrase must be the first line of the message or added as a header that can be read.

For anyone iwth a catch all email address it would work.

David Bolton

Another suggestion:

Send CC to abuse@?????