> When mail is delivered to a POP3 maildrop, envelope information is destroyed. To combat this, you would need to tunnel the enveleope information in headers.

> When mail is delivered to a POP3 maildrop, envelope information is destroyed. To combat this, you would need to tunnel the enveleope information in headers. Isn't that exactly what Envelope-to is supposed to be? Protocol-level data? It's not really part of the e-mail, but added when sending it. If you forward the mail to another machine, there will be a new envelope. I can see that it's all a gray-ish area with email (because email is a mess (which might be part of why it's been successful)) but I can't see a reason to complain about losing Envelope-to.