Exchange 2k on 2k Server.. In-place upgrade possible?

Ok I know someone is going to ask me this so I might as well get it out in the open.. I raised the functional level of the domain to 2003 native...not knowing a remote location still had a very old Exchange 2000 server running on Windows 2000 Server.  Now since the box isn't a Domain Controller..shouldn't it be just fine?

Answer to your question is yes.  See both links.

http://www.msexchange.org/tutorials/Upgrade_Exchange_2000_to_2003.html
http://support.microsoft.com/kb/822942

Yes I just read a MSFT article saying how it's unsupported.  Upgrading the Exchange from 2k to 2k3 is not an option as we've got an in-house invoicing app thats tied to Exchange 2000.  But now what about the 2003 native mode domain?  Can a Windows 2000 server still run unhindered as long as it isnt a DC?

If it isn't a DC, I don't think it is a problem.  I am looking around for a KB article to point that out specifically, but I am 99% sure.

This is the defintive KB article:

http://support.microsoft.com/kb/321648

Of course it would be more desirable to move to a new box, but it is possible to do what you ask.

Definitive of what?

Upgrading the OS to 2003 but leaving Exchange at 2000?  I don't think so somehow.

I also dont understand whats "definitive" about that KB article..especially since I did upgrade from 2000 to 2003 last night.  Oh well, thanks for the effort guys.