Its difficult to block messaging traffic because ICQ and other messengers are not stuck on a specific port. The only way you could do it is to block access to the host servers they register with. This will take a lot of trial and error while looking in the debugging logs to determine what servers to block address to. Good luck.
I thought the traffic came in on a public port 1-1025) and them was switched to an established session on a new port higher than public. can you get rid of ICQ and all chat for that matter by finding that port?
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...