Since the BCM database lives in SQL, it can't be on the Exchange server. The latest update that you can download from http://office.microsoft.com does provide some sharing capability, though.
FYI, there is a separate newsgroup for BCM issues -- microsoft.public.outlook.bcm

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Sue Mosher, Outlook MVP
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> Has anyone managed to get BCM database on the Exchange server so all
> users can see it?
>
> I'd much rather use it than the contact database as "contacts" are held
> under "accounts".