For those interested in using ADAM as a user authentication store for SharePoint 2007 you might want to check these out.  They will help with understanding as well as configuration.

How to use WSS v3 with ADAM for user authentication

SharePoint PeoplePicker Behavior with ADAM Users

Active Directory Application Mode (ADAM)

SharePoint ADAM Role Provider

Create your LDAP data store with the Active Directory Application Mode (ADAM) directory service

ASP.NET Provider Client Application

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