I have a client running Exchange 2003 on an ESX 4.1 server and I want to upgrade them to Exchange 2010. Their production host servers can run 64-bit vms, but their disaster recovery servers can only run 32-bit vms. Is it possible to restore Exchange 2010 mailboxes to an Exchange 2003 server in the event that I am forced to use a disaster recovery server? If it is possible, can you direct me to some detailed instructions? Everything I found talks of restoring Exchange 2003 mailboxes to Exchange 2010, not the other way around.
Thanks for your help.