If your system hangs when you are configuring SKIP and you do not have access to your machine, reboot your machine in the single-user mode and become root.
With a text editor, such as vi, edit the file acl.<network_interface> in the /etc/opt/SUNWicg/skip/ directory so that line
skiphost -i <network_interface> -o on
reads
skiphost -i <network_interface> -o off
to disable SKIP.
Reboot your machine normally to clean up the file system.
You, then, as root, may reconfigure your access control list as your security policy dictates.