I've got a problem with my POP3 provider delivering me e-mails with broken
Return-Path header. When it's long, it gets wrongly folded into multiple lines, in the middle of e-mail address like this:
Return-Path: <bounce-md_30050491.5f06fc4d.v1-e20857b41e04493380b808e01cb6b51 firstname.lastname@example.org>
Therefore, Postfix returns error and I get bounces from Fetchmail:
fetchmail: SMTP error: 501 5.1.7 Bad sender address syntax
I've read about Fetchmail's
-Z option, but I don't want to discard these mails, they are important and not spam.
Is there a possibility to make Postfix treat this special case gracefully and return no error message? Or maybe someone knows a better solution to this problem?