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I suppose the fact the virii could propegate using such medians as IM clients has been known for a while, although there was a low probability. Nobody thought about protecting against it like they did MS Blast, or the MyDoom's. The first virus on this "new" median, I predict, will either be huge, or small, then someone will make another, "better", virus to exploit the same exploit. I am not sure what exploits there are or could be for IM clients, but since I have a fair bit of free time I shall be investigating (PM me if you can help, or give me some hints on how to find expoits ^_^). The profile virus was quite minimal in that it was just a pain in the ass...

-Cheers-