system
19
Avast 2014.9.0.2011 gives a pop up (and blocks) all 4 of the eicar variants (.com/.com.txt/_com.zip/com2.zip) as shown in the attached screen shots, when an attempt to download them is made using standard protocol http.
As expected it does not block the download of any of the variants when the download is made using SSL enabled https, however it does subsequently detect them on a scan or if an attempt is made to extract from zip.