Leading dot incorrectly stripped

[drtrinidad]

I have Sendmail 8.10.1 installed on SCO OpenUnix 8 (the banner reads ESMTP Sendmail 8.10.1/UW7.1.1-NSCd)

Occasionally messages go through it containing lines consisting of a single dot, for example:

test
1
2
.
3

The sending SMTP program adds a second dot so that the dot will not be taken as the end of the message. The problem is, this installation of sendmail passes it on to the next SMTP host WITHOUT the second dot, so the message is cut off at the dot and looks like:

test
1
2

Is some configuration option causing this? I looked at 'IgnoreDots' but this seems to refer to a different situation (allowing you to pipe a file to the daemon).

FWIW, I also have sendmail 8.8.8 on SCO OpenServer 5.0.5 and Sendmail 8.11.6 on linux - neither of these installations have this problem.

Any suggestions appreciated!

 

[danielhozac]

The &quot;end of message&quot; is specified as <CRLF>.<CRLF> in the SMTP RFC. If the message contains this sequence, that is considered to be the end of the message. //Daniel

 

[drtrinidad]

Exactly - so as per RFC 821 under &quot;4.5.2. Transparency&quot; it states

1. Before sending a line of mail text the sender-SMTP checks the first character of the line. If it is a period, one additional period is inserted at the beginning of the line.

So my mail client (Microsoft Outlook) dutifully inserts the extra period into the sent text (I can see it in the sendmail debug log), sendmail strips it (which it ought to before delivering it locally) but it doesn't follow the above rule (ie adding another period) when passing the text on to another SMTP server.

My question is: how can I force it do to that?

Thanks in advance!

 

[drtrinidad]

Sorry, I had also meant to include these log excerpts for clarity:

incoming:
02408 <<<
02408 <<< 1
02408 <<< 2
02408 <<< ..
02408 <<< 3
02408 <<<
02408 <<<
02408 <<< .
02408 === CONNECT nexthost.mycompany.com.

outgoing:
02408 >>>
02408 >>> 1
02408 >>> 2
02408 >>> .
02408 >>> 3
02408 >>>
02408 >>>
02408 >>> .
02408 <<< 250 VAA00899 Message accepted for delivery

 

[drtrinidad]

Problem solved!

In /etc/sendmail.cf the mailer definition for SMTP was missing the X flag.

I found the solution in a usenet reply from 1994 from Eric Allman himself! I guess not too many people have this problem, though anyone using Caldera Open Unix 8 probably does.