Not to rain on Oscar's parade, but it looks like someone else did an AOLserver LDAP module back in Feb. 2000. Interesting that he found some conflict with it when AOLserver was also running the Oracle8 module (I assume that's not the aD driver--would similar issues apply?)

Read about it here

As far as LDAP in Tcl, well, this might be of some interest:

This is about adding a command to the Tcl interpreter so you can get access to the LDAP C library.

There's a Tcl shared library for LDAP on this page of LDAP software

And, just in case someone forgot about this, the ACS has an LDAP module too: see it here

(I don't know the licensing issues, etc., though this was done a while ago, so perhaps it would be GPL'd or whatever the original ACS license was?)

This message from openldap.org suggests that there is Tcl LDAP code from a guy at Neosoft (though when I looked through all the packages the LDAP packages seemed to be for Tcl 7.6, etc. and not the one this guy was talking about.

In any case, it does seem like there is some stuff out there to do LDAP with Tcl.