Hi my name is Eric Moyers. I work in the Cisco Small business Support Center. As I'm sure that you know, most SMTP traffic goes through port 25. Doing the upgrade to the new version should not have made any ports changes to your system. Please call the Small Business Support Center at 1-866-606-1866, and open a case with one of our Blocker agents. Im sure that we can determine the cause of your issue and help you get thing rolling again.
Thanks
Eric Moyers