LDAP proxy

Dear group, I manage the school network in which we have two separate MS-AD servers (one for teachers and the other for students). We also have mySQL database of our alumni. I would like to connect this three information bases to one "virtual" LDAP server (for authentication purposes on various LAMP web servers etc.).

Is it possible to configure such virtual or proxy server using OpenLDAP? And if yes, could anybody be so kind and redirect me to some how-to resources?

I was trying to search this using Google, but as I'm OpenLDAP newbie, I don't know the terminology exactly and my search results are not good.

Thanks in advance for any help

Jakub