How-to 'Restore' mailbox tree from file backup

[Bing Du]

> Hi,
> I have lost 80% of the folders in a hierachie of a "virtual" user´s
> mailbox.
>
> I have a backup of all files under spool/imap and lib/imap.
> This is a full backup 3 days old (which would be ok) and an 3 incremental
> backups from the last 3 days (which would be nice to have).
>
> There are a lot status and db-files, so I assume it will not work very
> good to just copy the files in the original directories.
>
> Is there a how-to to restore the information from a file backup?
>
> (I thought about setting up a second server, trying to get the lost mails
> there and copy the mails via IMAP-client to the main server, just to
> prevent the integrity of the database on the main server. The second
> server could be removed after this.)

I think those mail files should be just as other regular system files. 
After you restore them back to their original place, 'reconstruct'
(http://linuxcommand.org/man_pages/reconstruct8.html) should take care of
the rest.  If worse and more complicated than that, I'd like to hear other
inputs.

Bing