That depends on what software you're using.
Solaris 2.5 sendmail:
Fixed in Solaris 2.5.1.
You can fix the problem by putting ``,E=\r\n''
at the end of Mether, Mtcp, or Msmtp in sendmail.cf.
(Note that Mether is not the same as DMether.)
sendmail V8 has a bug that will produce a bare LF
in certain messages (e.g., messages with very long lines).
This bug was identified in November 1996;
I don't know if it has been fixed yet.
Eudora Pro 4.0 for Windows:
The HTML LF problem was fixed in 4.0.1.
The attachment LF problem was fixed in 4.1.
listproc 6.0c:
Chuck Foster says you should add ``CONVERT(buf);''
before ``WRITE_TO_SOCKET'' around line 165 of sysmail.c
in the Listproc source code.
fetchmail:
Recent versions of fetchmail reportedly do the right thing.
Make sure the forcecr option is on.
Galacticom WorldGroups:
Reported 19970716. No information yet on how it can be fixed.
Claris Emailer:
Reported 19980613. No information yet on how it can be fixed.
It is an ASCII linefeed (LF) character
not preceded by an ASCII carriage-return (CR) character.
Every line in an Internet mail message
is required to end with CR LF.
The entire message ends with CR LF dot CR LF.
822bis specifically prohibits other uses of LF.
The mail clients discussed above
are incorrectly ending lines with LF
and, in most cases, ending the entire message with LF dot LF.
That's not CR LF dot CR LF,
so a server such as msn.com
will sit there waiting for the rest of the message.
After a while it'll give up and drop the connection.
Your mail doesn't get through.
Some mail servers convert a bare LF into CR LF,
and accept LF dot LF
as the end of a mail message.
This behavior is specifically prohibited by 821bis.
SandyBeach will be happy to assist you in solving mail delivery agent problems.
Just contact us via email,
or call us at 206-789-9376.
Your customers will thank you.