BDC/PDC Problems When Upgrading To Windows 2000?

Kisc asks: "After being hired to administer Sun/Solaris machines, I find that my next big job is to get our network moved over to Windows 2000 Active Directory Services and Exchange 2000. We're on an NT 4 domain. I did it once... but it didn't work, due to undocumented problems with BDCs. We got a Microsoft tech support guy to finally admit that BDCs cause known problems when trying to upgrade your PDC to Windows 2000/ADS. I have read through three different books, and never found mention of that (including the O'Reilly book on ADS). Please, does anyone know of a book, set of books, a Web site, or anything, where I can get the information on Exchange 2000/ADS/Windows 2000 that Microsoft doesn't want me to have?"