Before a Zones system can be registered here, you must first bring it under Cloudmin's control using the Add physical system link under Add system on the left menu. It is possible for a single system to both host Virtualmin domains and Solaris, on a powerful enough system. You can register both Solaris X86 and Sparc systems, as long as they are running Solaris 10 or later. Once this is done, use the Register a system for Solaris Zones hosting link to start the registration process.