It is a common situation and when the account is removed from Domino Directory bad things cam appear, like this message:
[27718:00265-4009925536] 05/05/2010 11:39:10 AM Policies and settings documents signed by XYZ/Acme are no longer valid because this person does not have the required access level or roles to the Domino Directory.
It is about Policies and you solve the problem with this:
In the Policies (or Settings) view, check all policies you want to resign then choosed ‘Actions -> Resign Policy’
