Is your unattend.xml file in the image or do you use the inject script provisioning action?
The unattend.xml file on the image at this point. In fact I was able to get around this by adding the following command to the 'Pre-boot commands' section of my OSD script:
copy c:\unattend.xml c:\windows\panther\unattend.xml
This works because the unattend.xml file at the root of the C: drive has the actual computer name in it, not the %COMPUTERNAME% variable like the one in the \panther directory.
Ah, you use OSD scripting, not provisioning. My bad.
Can you post a copy of your OSD script?