I updated my S650 appliances last week to v6 and I have been having problems with my NAT configuration ever since. This may not be tied to the update, but no other changes were made. I use NAT to port SSL traffic to my webmail server while port 25 should still pass to my email appliance in my DMZ. Since the time of the update, my NAT does not work. My port 25 traffic will not pass to my email appliances unless I turn off the NAT to my webmail server (they both share the same outside IP address). I know there is still a great chance that this is not related to the v6 update, but I would like to know if anyone else has reported similar issues.