Warning php on force change password

[Postmaster]

Hi, I have add the plugins force change pasword to my roundcubemail . i use openldap (ldap_simple) When i connect to my roundcubemail with a user; i have a message to change my password after 10 days for example, the password was saved . But when i connect again : i have the same message (change the password). In mail.log i have this error:

**PHP Warning: ldap_search(): Search: Invalid DN syntax in /opt/www/roundcubemail-1.3.0/plugins/force_password_change/drivers/ldap_simple.php on line 45

Mar 7 09:37:09 mail1 roundcube: PHP Warning: ldap_get_entries() expects parameter 2 to be resource, boolean given in /opt/www/roundcubemail-1.3.0/plugins/force_password_change/drivers/ldap_simple.php on line 46

Thank's for help