http://blogs.technet.com/tnmag/archive/2008/08/29/inside-sharepoint-sharepoint-directory-integration.aspxPav Cherny discusses the limitations of the built-in Directory Management Service in SharePoint and explains how you can replace this component with a custom solution that lets you synchronize SharePoint recipient information with other directory solutions.en-USCommunityServer 2.1 SP1 (Build: 61025.2)