I’m confused now but I think not:
If on-demand, you just need to turn on archive scanning.
If on-access, avast by default doesn’t look for viruses in packed files. However, it can be enabled by the deftasks.xml file in the avast folder - all you need to do to enable scanning of archives on-access is to add the line
EXE;ZIP;MIME;RAR;ARJ;TAR;GZ
after the line
1
If you’re using avast 4 Professional, the same thing can be done in a more convenient way by editing the resident task.
This seems to be the last word of our Guru (http://forum.avast.com/index.php?board=2;action=display;threadid=15) ;D