23.3.1.1 To Configure Messaging Server for Cleartext Passwords

You can now configure Messaging Server so that it knows the Directory Server is able to retrieve cleartext passwords. This makes it safe for Messaging Server to advertise APOP, CRAM-MD5, and DIGEST-MD5:

configutil -o sasl.default.ldap.has_plain_passwords -v 1

You can disable these challenge/response SASL mechanisms by setting the value to 0.

Existing users cannot use APOP, CRAM-MD5, or DIGEST-MD5 until their password is reset or migrated (see to Transition Users).

Note that MMP has an equivalent option: CRAMs.