As far as we can tell through our research, they're using the same file location, but it also has the file locking enabled so that Outlook doesn't go all squirrelly. Though, even in our testing of Outlook beta, we'd get the database errors but no duplication.
The best explanation that we got is that it's a piece of legacy code that's hardcoded for that file path. Of course, the best solution would be to move it to where the Apple spec says it belongs (/tmp). A file being put in Caches assumes that it's a location that can get flushed with no detrimental effect on your software. In Microsoft's case, it's *very* detrimental. To the point where our Exchange environment had mailboxes that were 10X larger than they really should have been because of all the duplicates that Entourage was causing.
All because we were being good IT boys and girls and flushing user caches once a week (as part of weekly maintenance) to prevent support calls. Go figure.
j
