Operations error (??) in set_option(ld, LDAP_X_TLS, &arg)

["Yves Robin" <yves@reefedge.com>]

When trying to connect to openldap server,
i got error 1: Operations error in set_option(). What does this mean ?

Is LDAP_X_TLS the correct const to activate openldap session over SSL/TLS ?
I tested openldap server with :

ldapsearch -x -b dc=my-domain,dc=com -H ldap://localhost -Z "(cn=yves)"

and the response is correct.

thanks for lights.

Yves