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CSA rule for Port Sweep

I have a Network Shield rule that has "TCP/UDP port scan" checked, communicating with all IP Addresses using @local. It was generating a lot of junk events like this:

A portscan was detected Reason: ICMP unreachable. ICMP:> type destination_unreachable/03. The operation was allowed by a rule (rule defaults).

If I run Superscan against a test machine, I just get 1 event:

A portscan was detected Reason: TCP reset packet detected. IP: ->, protocol . The operation was allowed by a rule (rule defaults).

I know that there is a bug in causing the event to not include IP addresses, but its the event itself, or lack of, I'm concerned with.

I would like to create a more robust rule... something that gives me a clear indication of a port scan in progress.