On 05/08/2013 11:41 AM, Vincent Lefevre wrote:
Perhaps for IPv4 (but this depends: some people send mail to a few restricted people). If only the IPv6 address lacks a PTR, this is probably not true, at least in France, where the biggest ISP's don't support IPv6, so that there are no deliverability issues with them. Only with the few people who have a MX with IPv6 support.
Nope, I can tell your from experience that Comcast will reject your mail if you relay it from an IPv6 address that doesn't have a PTR.
Peter
