I have a seemingly identical problem to someone else who posted but I don't want to hijack his thread which is here:
I am wondering if creating an exception, such as one for "runescape.com" would be safe, or if it would expose my system to risk. I am wondering this because I would like to be able to play the game without the false detections, if that indeed is what they are. I also, am uncertain as to how to create an exception.
I believe I am and was at the time, running an up-to-date version of Java, Mozilla Firefox, Windows XP, and Avira Free Antivirus.
In case it might help, part of the Avira report read as follows:
C:\Documents and Settings\*****\Local Settings\Application Data\Sun\Java\Deployment\cache\6.0\0\7da392c0-365d8b36
 Archive type: ZIP
[DETECTION] Contains recognition pattern of the EXP/JAVA.Rafold.V.Gen exploit
[WARNING] Infected files in archives cannot be repaired
I altered one small part with these ***** out of caution.