The LDAP module in ACS, relies on LDAP inside Oracle. I don't think it will port to PG unless PG has that built in as well. From looking through the small amount of code, I don't believe the author had much of an understanding of LDAP.
LDAP has a well defined API in C. All the client libraries support this API. The result is that it is relatively easy to write an AOLserver C module and then switch out the actual library you use. I chose OpenLDAP.
One problem I ran into is that there is relatively no information on how to use LDAP. The authors of the software wrote a huge fat book _Understanding and Deploying Directory Services_ that is great for managers, but otherwise is a bookshelf hog. They also wrote _LDAP Programming Directory-Enabled Applications with Lightweight Directory Access Protocol_. I own that one as well and it is useful for working with the client library. I initially found most of this book online at the publisher website. (MacMillan Technical Publishing).
Again the problem is in the use. There is no simple logical method of translation from what most of us do with databases and permissions to LDAP. It isn't easy to draw up a schema, and permissions is just wacky.
I was able to get OpenLDAP setup so that I could use the server to store my Netscape Roaming Profile. Even that was a pain, because the original doc at Netscape was written in an outdated Schema format. I did find a howto (linuxdoc.org?), but I still had to deal with permissions on my own.
What we need is some real LDAP guru who can guide us through an example of how to use this beast.
My module compiles and doesn't eat memory. It can bind, authenticate and query, at least a little.
