Tony Finch wrote:
On Fri, 6 Apr 2007, John C Klensin wrote:
I don't know how many of them still exist in the wild, but there
was a time that a multiline opening greeting would cause some
clients to self-destruct.
There are a number of servers that have a multi-line greeting by default.
I've been running my server for years now with a multi-line greeting and
observed no interop problems (3M messages per week).
My customer support observations:
Since the time (circa 2003) we added the multi-line 220 system policy
template in our package as part of our overall SMTP AVS/security
enhancements efforts, I recall there some early but few interop reports
No doubt there are clients that continue to have problems. However, its
become a matter of "bad vs good". Good guys complain, report and
resolve issues. Bad guys don't complain, so they either evolve and
resolve client legacy issues or just ignore it.
Case in point:
The old PHP 3.0 internal "send mail" function was very simplistic and
was ignorant of multi-line SMTP server responses.
When used by GOOD intention operators, they reported the problems.
a) Upgrade to PHP 4.x/5.x, or
b) Disable their 220 Multi-line System Policy display.
When used by BAD intention mail blasting bulk spammers, they didn't
report problems. Solution:
a) Evolved to SMTP compliant operations, or