I have all of the companies address book in a sql database and migrating to LDAP is not a realistic posibility at the moment. So I need to make the GAL work from a SQL database. I've considered a number of ways to do this and I think the most practical is to use some kind of LDAP front end that essentally runs queries against my sql database.
Does such a thing exist? Has anyone done this before? Can anyone point me towards a good (preferably open-source) product?