The Unity folder is where we stick all our "custom" objects (hijacked mail users and custom recipients since Ex5.5 doesn't have an extensible direcotry schema really). These are hidden objects (i.e they have no display name) and correspond to all the Call Handlers, COS, Locations, Interviewers etc... you see in Unity in the SA.
There's no way to hide this folder from the Exchange administrator... it's going to be there. In 2000 it only stores location objects (the rest is in the local SQL server) and the folder only shows up under "advanced view" but it's still there in ADUK if you go looking for it.
The DistirbutionLists container is created by default and is the store where Unity will create DLs by default if you add them in the SA (and by setup, of course). You can force DLs to be created in other containers with a registry setting if you like. You can remove the DLs and this container but you want to be careful since in the case of the "Undeliverable Messages" DL, it's referenced in several spots in the registry and the Unity database and just toasting it will not be good. You'll run the risk of losing undeliverable outside caller messages (i.e. if someone tries to leave a message for a mailbox that is full in Exchange and it bounces it back... we need to know where to send it).
Jeff Lindborg
Unity Product Architect/Answer Monkey
Cisco Systems
lindborg@cisco.com
http://www.AnswerMonkey.net (new page for Unity support tools and scripts)
