Postwaster replied to enigma1's topic in SpamCop Reporting HelpSâ€pam which arrives via my backup MX is guaranteed to arrive via IPv6. However, I've not yet seen spam arrive at my primary MX over IPv6 without going via the backupâ€¦ (What's going on here? I type â€œSâ€pamâ€ â€“ capital â€˜Sâ€™ â€“ and it ends up as â€œspamâ€â€¦ aha, inserting a zero-width joiner â€˜fixesâ€™ itâ€¦)
I just hit this one. My MXes all have IPv6 addresses, and the backup MX forwards to the primary over IPv6. So spam received via the backup will need header mangling in order to be reported, and spam received â€˜directlyâ€™ may need header mangling. (Also, the primary does greylisting; yahoo.com retries a lot, but most justâ€¦ go away.) Personally, I'd consider the following substitutions to be fine even though the header text would be changed: Localhost: ::1 â†’ 127.0.0.1 IPv4 in IPv6 (example address): ::ffff:192.0.2.1 â†’ 192.0.2.1 I don't see anything which can be done about other IPv6 addresses (except, possibly, link-local being handled much like RFC1918 addresses?); but once SpamCop start handling IPv6, this will be moot.