The guest domain must run an operating system that is compatible with both the sun4v platform and the virtual devices presented by the hypervisor. Currently, this requirement means that you must run at least the Oracle Solaris 10 11/06 OS. Running the Oracle Solaris 10 1/13 OS provides you with all the Oracle VM Server for SPARC 3.2 features. See Oracle VM Server for SPARC 3.2 Installation Guide for any specific patches that might be necessary. Once you have created default services and reallocated resources from the control domain, you can create and start a guest domain.
To work around this problem, unbind the guest domain, remove CPUs until you have no more than 1024 CPUs, and then rebind the guest domain. You can then run the Oracle Solaris 10 OS on this guest domain.