Using OS X and vmware Fusion. Requires an actual Solarish system or VM to modify the boot_archive.
Why would you want to do this? Well, it's an easy way of modifying an excellent platform for your own nefarious ends. Maybe you want to inject some extra (or less) work into the install scripts. Or just add some extra default services. Or drop in some leet figlet
into /etc/issue
. Or more usefully: Drop your application bootstrapping code into the platform to create turnkey appliances.
Download and decompress the SmartOS VMware image.
Copy the boot image out of the VM directory and mount it.