At 7:52 -0500 2003/03/31, William Thompson wrote: >
>I'm not sure about HELOs that are IPs. How many legit email would be
>blocked by that?
FWICT it is acceptable to either send an hostname that resolves to
the IP address of the host, or an ip address (after all you do not
need to own a domain to set up an outgoint only mailserver).
I think somewhere is stated that this is a MUST condition.
I do not know however if it is acceptable to refuse an email (not to
postmaster) if the above condition is not satisfied.
Some RFCs tend so be quite relaxed to make protocols more
robust/tolerant, in other words they may say: "you MUST not oppress
your own people" but at the same time "you MUST not invade a Country
even if it does not meet the first condition"...
