They said that the Apple EULAs allow virtualizing Server versions of Mac OS X only.I would have thought I'd seen them chime in on this.
Try it and find out. Maybe try installing it like it you would on a real PC (which is also against the EULA). Those methods usually require the PC to have similar hardware to a Mac though. The Parallels hardware might not be similar enough?Can you install Snow Leopard on a VM with Parallels Desktop?