A year ago I built a new machine and purchased "Microsoft Windows Vista Ultimate SP1 64-bit for System Builders - OEM" from NewEgg.com. I would like to upgrade to Windows 7 64-bit but I also need to a run a 32-bit Windows 7 virtual machine (inside VMware) to use some VPN software that isn't supported on Windows 64. Can I purchase an upgrade license for Windows 7 and still install 64-bit for my host OS and 32-bit for the guest OS inside the VM? Based on the Windows 7 SKUs over at NewEgg it looks like the OEM licenses are for either 32-bit OR 64-bit but not both.
UPDATE: Thanks to Wil and Molly for the answers they've posted. I have applied strike-through to my incorrect assumption below. Unfortunately the accepted answer to the question linked below is NOT correct and I have posted a comment encouraging that a different answer be accepted.
With respect to the legality of running Windows 7 as both host OS and guest OS inside of a VMware, I already found this helpful article that indicates it's legal, so no concerns there.