Well you problem is that in the document you referenced we actually say that you should use the same machine name
The computer name, Windows directory and the file system (NTFS) must be the same as the previous Windows installation.
There is a possible (use at your own risk) option that might work for the System State restore which is
Do a redirected restore for the System State and specify \\ServerName\System?State as the path
However even if this works - you would not want to bring Exchange 2007 back onto another server in the same active directory as your live Exchange server (which if this works and you reboot it would be) so for this test you should really be considering a separate copy of your domain in an offline network environment and to keep the machine names the same.