Quoting Marc Perkel (marc@???):
> >> Another feature - something I've asked for before - is the ability to
> >> treat a 5xx error as a 4xx error. I know people have complained it
> > Adding to code to break the fundamentals email, no matter how innocent
> > the reason, isn't going to make it into the main source code.
> However there are legitimate reasons not to always honor 5xy codes
> when you KNOW the reason it is being rejected is a mistake.
In such a case, when you KNOW there's something wrong with the receiving
side, wouldn't it be better for your host to hold all mails to that
server alltogether?
Like with the 'hold_domains = domainlist' configuration setting?
Or some lookup in your routers that fails if the domain is in some
fail-list?
There's tons of other options besides mangling the source to deviate
from RFC-standards.