When the value of tmnxUserPasswordEncrypted is 'true', the
password specified by tmnxUserPassword is in the encrypted
form.
When the value of tmnxUserPasswordEncrypted is 'false', the
password specified by tmnxUserPassword is in plain text.
tmnxUserPassword and tmnxUserPasswordEncrypted, which indicates
whether or not the password string is encrypted, must be set
together in the same SNMP request PDU or else the set request
will fail with an inconsistentValue error.