I'll bump this a bit for Richpowell's sake as I am also a multi-user application developer using the SmartFox server.
First of all, the SmartFox server (
www.smartfoxserver.com) is an XML socket server which allows primarily flash made applications to connect to it and thus make them multiuser (like multiplayer games etc). The default port that smartfox is listening for connections at is 9339. I set SmartFox on a dedicated server and had it run on port 80 in order to allow people who are behind firewalled environments (like workplaces) to access our games and not be blocked. The data that are being transfered back and forth between SmartFox and the clients are pure text, XML, JSON or simple text formatted.
Now, I get a lot of traffic on my server and for the past couple of years I have been getting a lot of complaints from people who were unable to connect. After some digging through I found out that the vast majority of them were using Avast. Adding my SmartFox server's IP address to the exclusion list of the Web Shield in Avast 4 would do the trick and allow people to connect to my server just fine. Unfortunately this is not the case with Avast 5, where no matter what I put in the exclusion list, the Web Shield will always block the access. The only way to connect is totally disabling the Web Shield, which even though I have absolutely no hesitation to do, I cannot in a sound mind advise my users to follow as a practice.
Also, SmartFox sports a fallback http connection method on a different port (443 in my server), but it's limited to 10 concurrent users, so sometimes (especially late at night where there are few only connected) you can connect to the game through the fallback method even if the WebShield is active... if you're lucky to find an empty slot.
I'm willing to provide any assistance and data, if I were directed to the right person from Avast so we can solve this issue that has been going on for more than 2 years now.
The app if you want to check it out and see what's going on is published as a facebook app here:
http://apps.facebook.com/tavli_me (it's a backgammon game, default language is greek but you can switch it to english).