F-Prot - Frisk Software's f-prot virus scanner - is a Dos/Windows thing which is also available for GNU/Linux.
The virus definitions who are shipped with various Linux distributions are generally old and out of date. Thus; you want to update them (regularly) if you want to use f-prot for scanning incoming e-mail, etc.
You could put something like this update-fprot.cron script in your /etc/cron.weekly to automatically update your F-Prot virus definitions.
#!/bin/bash for f in macro.def sign.def sign2.def;do wget ftp://ftp.f-secure.com/anti-virus/updates/f-prot/dos/$f if [ -f "$f" ];then mv -v $f /opt/f-prot/`echo $f|tr a-z A-Z` fi done
The "official" download page is http://www.f-secure.com/download-purchase/dos_updates.shtml and EU users can/should replace the above wget path with ftp://ftp.europe.f-secure.com/anti-virus/updates/f-prot/dos/