My firewall has detected infection by Trojan backdoor-g-1. It uses port 1243. Neither Symntec nor McAfee has a definition or recognition of this Trojan. Have you heard of it? What do you know of it?
My general rule of thumb when confronted with a new virus, Trojan or worm, is to take a look at what a number of antivirus companies are saying about it.
Searching on Google is a good way to find out if someone has written something, and most antivirus and other malware-detection companies now offer online encyclopedias one can search. One problem that arises is that antivirus companies, after complaints from users for more than 10 years, still do not use the same name for each critter. Maybe the user community needs to start a petition?
In any case, you should be aware that antivirus software is not generally the best at detecting Trojans. There are more specialized companies working in this arena, such as PestPatrol and Spybot.
Not knowing which firewall you are using, it would seem that it has detected "Backdoor/SubSeven Trojan". Here is some info on it: http://www.europe.f-secure.com/v-descs/subseven.shtml
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