Most 4D v11 SQL products are not platform specific until the time they are registered. Once the product has been regsitered on a particular platform (i.e. Windows or Mac), the license will be tied to that platform and will not be able to be registered on the other platform.
For example; if you run Windows XP through Parallels on a Mac OS X system, and then register your product in the Windows XP virtual machine; that license will have become a Windows only license and will never be able to to registered on a Mac machine. Attempting to register the product on any other platform will yield the error message:
This is expected as the platform the license was registered on is different than the platform it is currently being registered on.