Even though I'm the admin of our groupware-server, I cannot read e-mails of other employees (unless they themselves gave me proxy-rights to their mail-account or shared one of their mailfolders with me). But I can download all e-mails which were put in quarantine. German law prohibits employees (including admins) from reading other people's mails. You could be jailed if you do so.
I would like to have the mail download feature disabled. Even better if mails were stored in an encrypted format an the ASGs hard drive, to make it impossible for admins to read other people's mails.