Issue password encryption for mail users and roundcube error log

[ESTUGO]

Hi there,

i use CentOS 7.2 with Plesk 12.5 MU#52

I have found the PLAIN TEXT password for mail_users in:
/usr/local/psa/admin/bin/mail_auth_view and in /var/log/plesk-roundcube/errors!

/usr/local/psa/admin/bin/mail_auth_view
Authentication database contents:
+--------------------------------------+-----+--------------------------------------+
| address |flags| password |
+--------------------------------------+-----+--------------------------------------+
| info@naeh | | PASSWORD in PLAIN TEXT |
| info@naeh | | PASSWORD in PLAIN TEXT |


cat /var/log/plesk-roundcube/errors
[04-Nov-2016 21:46:16 +0000]: <975ij0pc> IMAP Error: Login failed for info@naeh-******.de from **.90.**.**(X-Real-IP: **.90.***.***). AUTHENTICATE CRAM-MD5: A0001 NO Login failed. in /usr/share/psa-roundcube/program/lib/Roundcube/rcube_imap.php on line 193 (POST /roundcube/?_task=login&_action=login)
#2 /usr/share/psa-roundcube/index.php(118): rcmail->login('info@naeh-****...', 'PASSWORD in PLAIN TEXT', 'localhost', true)

1) It´s not a migration from other server!
2) How can i force password encryption"Flag E"?
3) Why does logged roundcube passwords in PLAIN TEXT !?

Many thanks in advance


Erik