Is it possible to replicate a translucent proxy?

In our project we have a central LDAP repository that is populated with generic information about our collaboration and its users. This is replicated out to various sites in a master -> slave setup via syncrepl. At the sites we may need site local information. We have been addressing this via a translucent overlay.

However it would be nice to have some redundancy on the translucent overlay.

What is the best way to approach this?

My ldap servers (including the translucent proxy) are on CentOS 5 running OpenLDAP 2.4.18 (built from source). The master is running on a Debian system on 2.4.x.