That malware name is generally an indication that the site has been hacked, there have been many of these in the forums and all of those that I have investigated have been good detections.
Having just checked that url the site has been hacked, there is a large chunk of obfuscated javascript (hiding its intention) after the closing html tag a standards, no, no and highly suspicious. The code is on a single line rather than laid out conventionally, I have broken this down in the image to make it easier to see. This line goes on for a considerable bit longer.
Re: the lack of a pop-up, try a repair of avast. Add Remove programs, select 'avast! Anti-Virus,' click the Change/Remove button and scroll down to Repair, click next and follow.
Do you get an alert on this link, it is a harmless test file ?
Web Shield Test -
http://www.eicar.org/download/eicar.com