Two days ago, I downloaded Avast! 4.5. On my first scan, Avast! picked up Win32:beagle-aw. I took the recommended action which was to send it to the vurus chest.
It is a worm - a google search for Win32:beagle (this will give more information on the beagle family rather than a variant) should return more hits if you are interested.
It is harmless in the chest, this gives time to investigate. From the chest it can be restored or deleted as required. Generally you should leave it there for a short period of time and ensure that there are no adverse effects on your system.