Good to know it's benign.
Can I further assume that the only reason it hasn't popped up until now is because previous scans ignored it - it not being a Mac issue?
Sophos did not identify the [restored] file as a problem so it appears the false positive issue is just with ClamXav.
Thanks for the update, that's pretty much what I suspected. To follow up on the other comment and question,
BC.Exploit isn't necessarily benign, but chances that it will affect you are small. You'd have to run the target MS software under susceptible versions of Windows on your Mac.
I also don't think you can assume that 'it' was ignored until now by ClamXav, assuming that the recent malware call was valid. Because of the scarcity of Mac threats, Mac anti-malware for the longest time has been mostly involved with detecting and neutralizing Windows threats, as they may be passed on unnoticed by Mac users via email etc. The issue of false positives (which seems what's happening) is likely caused by errors in ClamXav's signature file update.
