Dear Slugga,
I too faced the same problem in restoring individual mail box in exch.5.5. I had done following things and i succeed in restoring the individual mail box.
Create a Default mail box(just a base mail box).
Run Directory service available in server option.Before executing the restore command, you have to run this.
You can able to restore the individual mail boxes. Restored mails are kept under the separate folder called
"RESTORE ITEMS"
All the best
regards
badri
kgb@sundaraminfotech.com
(visitor)