It appears you can turn the Leopard firewall on or from the command line with this command:sudo defaults write /Library/Preferences/com.apple.alf globalstate -int 1The last value represents the state of the firewall, where:0 = off1 = on for specific services2 = on for essential servicesThere are other settings in the /Library/Preferences/com.apple.alf.plist file that you can explore and test to control other aspects of the firewall.

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