For those of you who use libcurl in your own applications, you may be interested to know that I've written a new LDAP implementation for libcurl.
http://article.gmane.org/gmane.comp.web.curl.cvs/13393
The old code had a number of problems, mainly due to exclusively using the synchronous LDAPv2 APIs, which prevented it from playing nicely in the otherwise fully-asynchronous libcurl framework. It also has a bug such that it always opens two connections to the LDAP server for every curl request. The old code is still there, for deployments stuck with older LDAP libraries (OpenLDAP 2.3, or non-OpenLDAP code).
The new code is fully asynchronous and non-blocking, written for OpenLDAP 2.4. It's also (surprise, surprise) far more efficient in parsing results. To cut down on duplication of config code, this module uses libcurl's existing socket and SSL infrastructure, instead of OpenLDAP's built in SSL/TLS support. Thus it automatically supports all of the libraries and features libcurl already supports, without needing any ongoing maintenance for when new libcurl features are added.
If you've got other tools already built around curl, you'll get improved LDAP support without making any other changes. If you're looking for ways to tightly integrate libldap support directly into your own applications, the libcurl OpenLDAP code can show you how.