another way to connect with ZEND auth ldap
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I want to connect to a ldap server. I've done it by using the following code in application.ini

    ldap.server.host = ldaps://ldap.example.ro
    ldap.server.username = "uid=admin,ou=people,dc=example,dc=ro"
    ldap.server.password = "password"
    ldap.server.baseDn = "ou=people,dc=example,dc=ro"
    ldap.server.bindRequiresDn = true

and then 

        $auth = Zend_Auth::getInstance();

        $config = new Zend_Config_Ini(APPLICATION_PATH . '/configs/application.ini',
                                    'production');
        $options = $config->ldap->toArray();
        //unset($options['log_path']);

        $adapter = new Zend_Auth_Adapter_Ldap($options, $username, $password);

        $result = $auth->authenticate($adapter);

Is there any way that i can do the same thing just without admin and password ?
without ldap.server.username and ldap.server.password