Hmmm, I think that ArPaNET has an interesting point:

First I would make sure that it isn't picking up something false, this particular trojan consumes internet bandwidth, won't allow registry editor to open, and displays false error msgs, etc... so check and see if these symptoms occur.
http://www.emsisoft.com/en/software/free/

Is a tool I would consider using. It scans for all sorts of malware and in particular it looks for "traces" as well as the full-blown article. Not all anti-malware get rid of these "traces" so you keep getting warned, but aren't really infected.