Windows 7 - SBS 2003 R2 in virtual machine?

I am having problems getting SBS 2003 R2 to work in either virtual PC or vmware player on a Windows 7 64-bit host. But it works on a Windows 7 32-bit host.

Here are the details: I have a backup of a SBS 2003 R2 server made by Symantec System Recovery 2011. With either host, I can create a virtual machine, boot the SSR rescue disk (from ISO file), and restore the backup to a virtual machine. I restore using the option for dissimilar hardware.

With the Windows 7 32-bit host, all works well, the virtual machine boots, and SBS 2003 goes through a mini-setup and works.

With the Windows 7 64-bit host, the backup completes, the virtual machine boots, a Windows logo on black screen is displayed for a short time (as usual), then the screen then goes black and is followed by a BSOD STOP: c0000021a - The session manager initializaion system process terminated unexpectedly with a status of 0x00000263 (0x0 0x0).

This happens with both Virtual PC and VMWare Player.

I can restore a backup of a Windows XP Pro system to a virtual machine successfully on the 64-bit host.

Has anyone run SBS 2003 successfully on a 64-bit host?

Is there any reason I should expect this not to work?