Ok, it is always a good idea to go to the website of the antivirus vendor (grisoft in your case) and look up the information for that trojan. Often, they will list other places to to look for it, and which registry entries it makes. This can help to delete it. If they list names given from other vendors, symantec's website usually has the best removal instructions, however they will have named the trojan differently.
It is important to remember that a trojan is NOT a virus, it is a trojan. Most trojans dont hurt your computer, they change and lower your security settings, causing more harmfull things to occure, or to let people in. After finding a trojan, always double check your antivirus, firewall, and browser security settings. you may find they have all been turned off or switched to low - allowing something or someone else access.
while your at it, its a good time to check for spyware and such. check your start up items in msconfig to see if there is a host process that is still lingering in your computer and of COURSE, update your avg. running a scan in safe mode neever hurts anyone.