Shorewall users - Dec 2003 - ICMP

I was just running ''shorewall monitor''  and found the
following:

Standard Chains

Chain INPUT (policy DROP 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out  source   destination
    0     0 ACCEPT     all  --  lo     *    0.0.0.0/0  0.0.0.0/0
    0     0 DROP      !icmp --  *      *    0.0.0.0/0  0.0.0.0/0 state INVALID

What does this mean, where it says !icmp state INVALID??

---
Intuition, however illogical, is recognized as a command prerogative.
   -- Kirk, "Obsession", stardate 3620.7

Ted Gervais
Coldbrook Nova Scotia
Canada B4R1A7

Hello,

Did a google search ... 

http://lists.shorewall.net/pipermail/shorewall-users/2003-September/008755.html

Francesca