A bug for this already exists:
Bug 15378 - Obviate the need for and disallow LDAP anonymous binds
It is not currently resolved. You can with 5.0.0 and up work on disabling anonymous access to most things by manually customizing the ACLs. I think what you are really trying to do is also tied in with:
Bug 16601 - Secure Access To LDAP
So you have secure connections without anonymous binds.
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