Cannot LOGIN using openssl s_client

[James B. Byrne]

OS          : CentOS-6.9
Name        : cyrus-imapd
Arch        : x86_64
Version     : 2.3.16
Release     : 15.el6

We have a working Apache-2.2 /Squirrelmail-1.42 (SM) / Cyrus-IMAP-2.3
(CI) setup.  SM and CI reside on different hosts.  We use TLS over
port 993 to communicate.  The login mechanism is plaintext
authenticating against /etc/passwd.

We are in the process of transitioning from this setup to one hosted
on FreeBSD and I am having problems getting SM on the new host to
connect to the existing CI service.  To debug this I am using openssl
s_client as follows:

openssl s_client \
  -connect imap.hamilton.harte-lyne.ca:993 \
  -CApath /usr/local/etc/pki/tls/certs

Resulting in:
. . .
    Start Time: 1524836386
    Timeout   : 300 (sec)
    Verify return code: 19 (self signed certificate in certificate chain)
---
* OK [CAPABILITY IMAP4 IMAP4rev1 LITERAL+ ID AUTH=PLAIN SASL-IR
COMPRESS=DEFLATE] inet07.hamilton.harte-lyne.ca Cyrus IMAP
v2.3.16-Fedora-RPM-2.3.16-15.el6 server ready

LOGIN testusermb testuserpw
LOGIN BAD Please login first

According to the documentation the message LOGIN BAD means that the
arguments to the LOGIN command are not understood.  But, as far as I
can discover, the LOGIN command only takes two arguments: user name
and password.

I get the same results on both the new SM host and the old so the
issue is with my employment of s_client.  How does one connect to a
mailbox using s_client?


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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
Hamilton, Ontario             fax: +1 905 561 0757
Canada  L8E 3C3