As already mentioned in the Bug 760060,
OpenSolaris doesn't support 32 bit SPARC machines, so you should use a
qemu-system-sparc64 and not qemu-system-sparc.
(Although booting [Open]Solaris to the command prompt is not possible
with qemu-system-sparc64 yet)
Also --enable-kvm makes no effect when
Public bug reported:
The latest git version of qemu (commit
420b6c317de87890e06225de6e2f8af7bf714df0) fails to boot the OpenSolaris
image from http://dlc.sun.com/osol/opensolaris/2009/06/osol-0906-ai-
sparc.iso.
qemu-img create opensolaris 3G
qemu-system-sparc -hda opensolaris -cdrom osol-0906-ai
