I want to deny (DROP) a single local ip from accesssing a linux WORKSTATION
on a small LAN. Others host on the LAN have access. I would like to set up
the rule using the Firewall2 GUI as opposed to using the iptables command
line interface. I do see a "custom rule allowing dialogue" (for allowing
ports only) but nowhere in the GUI can I find a place to add the rule.

Could some one please tell me what the rule would be (something like -A
INPUT -s 192.168.x.x -j DROP ) and how to input it using the GUI.

PS I know that I could just add this to hosts.deny but for the sake of
constancy I prefer the approach outlined above.

Thanks for your help!