Distribution groups migrated from Exchange 2003 (to 2010)

In a migration from Exchange 2003 to Exchange 2010 we are now looking at distribution groups and the management of.

In exchange 2003 you could assign a manager specific to the group but now with RBAC it seems the only option is to give someone 'recipient management' permissions.  This obviously gives more permissions than just changing a few distribution groups.

Is there another way to do this so the management of of each distribution group is more specific only to these groups and not giving permission to manage all mailboxes.

Cheers

DE