GNOME was up-revved from 2.26 (snv_123) to 2.28 (snv_124).

If like me you love the new login sound which came with Nevada build 124, here's how to change it.

Here is the config file which specifies the startup sound.

/usr/share/gnome/autostart/libcanberra-login-sound.desktop
----------------------------
[Desktop Entry]
Type=Application
Name=GNOME Login Sound
Comment=Plays a sound whenever you log in
Exec=/usr/bin/amd64/canberra-gtk-play --id="desktop-login" --description="GNOME Login"
OnlyShowIn=GNOME;
AutostartCondition=GNOME /desktop/gnome/sound/event_sounds
X-GNOME-Autostart-Phase=Application
X-GNOME-Provides=login-sound
----------------------------

Mount your old boot environment and copy over the snv_123 or earlier "desktop-login" sound file.

I'm using the SXCE Solaris distro, OpenSolaris paths will differ.

cp /.alt.zABE//usr/share/sounds/freedesktop/stereo/desktop-login.ogg /usr/share/sounds/freedesktop/stereo/desktop-login-trad.ogg
Run the command to test this and then modify the config file to match.

/usr/bin/amd64/canberra-gtk-play --id="desktop-login-trad"