Hello -
I can tell you from our experience we elected not to integrate CallManager with AD, and by that I mean install the schema updates that permit CallManager to create AD users when adding users in CCM. We are one domain in a multiple domain forest that, for obvious reasons, needs to manage who makes updates to the schema. Now, for Unity, if you are using Exchange 2000 for your information store (subscriber mailboxes will be on Exchange 2000), then by default you must integrate with AD. We worked with the root domain's enterprise admins (also the schema admins) to install the schema updates needed for Unity prior to 4.0(3) and needed for the new Unity bridge 3.0(1). However, we minimized the permissions Unity needed by only importing existing AD users into Unity, so we do not create AD users. And the 4.0(3) permissions wizard is too cool in that it allows you to tell Unity the specific mail stores you will be using for Unity subscribers. The degree of integration choice you make depends on the amount of latitude you have in your AD forest, and whether or not your Unity admin is also an Exchange admin/Domain admin and do you want Unity to create users in AD. Regardless, the integration between Unity and Exchange is a tight one, and coordination with the domain admins/Exchange admins if they are not the Unity admin is KEY to success. Lastly, if you haven't already, check with the IP Telephony forum, you may have more success with that audience who have implemented CCM with AD. Here is a link that may be of value -
http://www.cisco.com/en/US/customer/products/sw/voicesw/ps2237/products_implementation_design_guide_chapter09186a00801187c6.html
Best wishes,
Ginger
