oh hey Mark23,
You can get Roundcube 0.8.1 to work with CRAM-MD5 for IMAP and SMTP authentication.
in config folder just edit main.inc.php and make necesary changes at the following lines:
FOR IMAP
----------------------------
$rcmail_config['default_host'] = 'ssl://mail.yourserver.com';
// TCP port used for IMAP connections
$rcmail_config['default_port'] = 993;
// IMAP AUTH type (DIGEST-MD5, CRAM-MD5, LOGIN, PLAIN or empty to use
// best server supported one)
$rcmail_config['imap_auth_type'] = 'CRAM-MD5';
FOR SMTP
-----------------------
$rcmail_config['smtp_server'] = 'tls://mail.yourserver.com';
// SMTP port (default is 25; use 587 for STARTTLS or 465 for the
// deprecated SSL over SMTP (aka SMTPS))
$rcmail_config['smtp_port'] = 587;
// SMTP username (if required) if you use %u as the username Roundcube
// will use the current username for login
$rcmail_config['smtp_user'] = '%u';
// SMTP password (if required) if you use %p as the password Roundcube
// will use the current user's password for login
$rcmail_config['smtp_pass'] = '%p';
// SMTP AUTH type (DIGEST-MD5, CRAM-MD5, LOGIN, PLAIN or empty to use
// best server supported one)
$rcmail_config['smtp_auth_type'] = 'CRAM-MD5';
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