Cannot signal shutdown of Linux from z/VM (z-series)

Issue

• Red Hat Enterprise Linux 6.4 s390x is running under z/VM.
• Found the documentation for allowing z/VM to signal shutdown a zLinux instance (IBM cookbook).
• Its has been enabled signals for the instance on the VM side, and also the file /etc/init/control-alt-delete.conf has been updated to -h now, However, when the signal is sent, absolutely nothing happens on the instance. It appears to not even acknowledge it was sent.