What power should be delegated to an Asistant Admin(s) to allow them to be able to modify Exchange 5.5 distribution lists membership of a user account?
Directory and Resource Administrator 6.x
Directory and Resource Administrator 7.x
Microsoft Exchange 5.5
In order for an Assistant Admin to be able to add\remove a user account's mailbox from an Exchagne 5.5 Distribution List, the Assistant Admin must be granted the Distribution Lists - Modify a Mailbox power in Directory and Resource Administrator 6.x and the Modify Exchange 5.5 Distribution List power in version 7.x. This power must be granted to an Assistant Admin in the same ActiveView which includes the user account.
For more information on this topic, please refer to the following Knowledge Base article:
NETIQKB34116: How do I manage Microsoft Exchange 5.5 distribution list membership using Directory and Resource Administrator?