I am using Entourage 2004 and have just experienced something similar. My Database file grew to over 4GB and now causes a full application crash when I try to open it.
In order to open the application, I must delete all preferences, rename the identity, and create an new identity that is empty; however, I can find no way to import my old stuff into the new DB?
Does anyone have any suggestions on how to recover this?
The mail fortunately I have backed up by forwarding all my mail to an archive account which is downloaded into Mail (a better mail app, but not a full PIM). However, I have eFax and all my faxes are lost, as well as all my other attachments, rules, notes, project specific data etc.
I keep nightly backups of my whole home directory via rsync incremental, but have not been able to find a DB that can survive the backup process and restore correctly. So far, I have gone back about 2 weeks and still no luck.