I've run the command /usr/bin/canberra-gtk-play --id="desktop-login" --description="GNOME Login"
in a terminal and it did something, but I did not hear any sound.
There are 2 possible workarounds:
Experimenting with the --volume
option (did not work for me)
You can change the command to /usr/bin/canberra-gtk-play --id="desktop-login" --description="GNOME Login sound" --volume=10
and see if you can hear anything then. Higher values are possible.
Changing the login sound command entirely (worked for me)
You can create a startup application as indicated by Basharat and as command use this: paplay /usr/share/sounds/ubuntu/stereo/desktop-login.ogg
For Name and Comment, you can fill in what you want.
I hope that could help.
EDIT: I've used the wrong quotes first, but I still hear nothing when I use /usr/bin/canberra-gtk-play --id="desktop-login" --description="GNOME Login"
in a terminal. So the command definetly doesn't work for me.