MS Exchange 5.5

I just migrated to 2003 Exchange server from Exchange 5.5. I moved all mailboxes to new server through ADC connector. Just when I thought everything was working fine, my disk on the new server crushed before I could make a backup. I did not have backup on the Exchange 5.5 server. Now how can I rebuild the mailboxes on the old server because the .edb file still shows the same size file and the server(Exc. 5.5) mounts the Information Store very well except there is now no mailbox listing because they have been moved to the crashed server. Urgent!!!!