>>>>> "Eric" == Eric S Raymond <esr@???> writes:
Eric> First, a question. Is anybody here expert enough with
Eric> sendmail/smail/qmail/exim to know what can cause them to reject a MAIL FROM
Eric> address?
exim can be configured to be quite picky. In that case, it will
refuse to accept mail from any address that it can't find a route back
to. I suppose this normally means do a DNS lookup, and try to find a
valid MX or address record corresponding to the MAIL FROM. I don't
know if exim goes any further to verify.
