Archive file containing info from multiple users mailboxes

In an archive file, is there a way to determine what users
mailbox an item (calendar entry, email, etc.) was moved
from, into the file?

I have Outlook 2k in an Exchange 5.5 environment. I had
Outlook, mistakenly, set to auto-archive. That Outlook is
used to open many of my users mailboxes. Now data from
about 10 different user's mailboxes is contained in
one .PST file.

The data in the file is not separated by user (e.g. all
calendar items for all users are in the one calendar
folder). The only field that comes close to helping me is
the "Organizer" field, but it doesn't solve my problem.
Also, Inbox messages may not include the recipients name,
or there may be multiple recipients, so I can't just look
in the "To" field. I also have Tasks and Journal entries.

Thanks for any help you can provide.

brian