In <200506271800(_dot_)29866(_dot_)julian(_at_)mehnle(_dot_)net> Julian Mehnle
Ok, here's what it's about:
| 5. Mechanism Definitions
| When any mechanism fetches host addresses to compare with <ip>, when
| <ip> is an IPv4 address, A records are fetched, when <ip> is an IPv6
| address, AAAA records are fetched. Even if the SMTP connection is
| via IPv6, an IPv4-mapped IPv6 IP address (see [RFC3513] section
| 2.5.5) MUST still be considered an IPv4 address.
This is technically correct, but slightly unclear with regard to how
implementations should go about handling IPv4 and IPv6 addresses.
Ok, something else I've been pondering about IPv6...
In the above text, we *only* talk about IPv4-mapped IPv6 addresses and
not IPv4-compatible IPv6 addresses.
Is this correct?
It is my understanding that IPv4-compatible IPv6 addresses are just
special IPv6 addresses that have their lower order bits match certain
assigned IPv4 addresses. So, not every IPv4 address is allowed to use