delete specific mail in all folders

[Gerald Nowitzky]

Hello!

I have been confronted with a request today: We are running cyrus as imap 
server. We have currently about 3 million files and 150GB in our mail dir. 
One user has accidently sent something confidential to all users via a list. 
The request was, of course, to delete the mail from all mailboxes. Is there 
any reasonable approach to do something like this?

Thanks!
(Gerald)