Missing Decoders

[Carlos Mennens]

Last night I stood up a new server running Debian Linux 6.0 (i386),
Amavisd-new 2.6.4-3, Postfix 2.7, & Clamav 0.97. Now that I have
Amavisd-new running with all the other applications, I show multiple
'Amavis' notifications in /var/log/mail.log:

Mar 26 17:00:00 mail amavis[1020]: Found decoder for    .Z    at /bin/uncompress
Mar 26 17:00:00 mail amavis[1020]: Internal decoder for .gz
Mar 26 17:00:00 mail amavis[1020]: Found decoder for    .bz2  at /bin/bzip2 -d
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .lzo  tried: lzop -d
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .rpm  tried:
rpm2cpio.pl, rpm2cpio
Mar 26 17:00:00 mail amavis[1020]: Found decoder for    .cpio at /usr/bin/pax
Mar 26 17:00:00 mail amavis[1020]: Found decoder for    .tar  at /usr/bin/pax
Mar 26 17:00:00 mail amavis[1020]: Found decoder for    .deb  at /usr/bin/ar
Mar 26 17:00:00 mail amavis[1020]: Internal decoder for .zip
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .7z   tried:
7zr, 7za, 7z
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .rar  tried: unrar-free
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .arj  tried: arj, unarj
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .arc  tried:
nomarch, arc
Mar 26 17:00:00 mail amavis[1020]: Found decoder for    .zoo  at /usr/bin/zoo
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .lha
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .doc  tried: ripole
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .cab  tried: cabextract
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .tnef
Mar 26 17:00:00 mail amavis[1020]: Internal decoder for .tnef
Mar 26 17:00:00 mail amavis[1020]: No decoder for       .exe  tried:
unrar-free; arj, unarj
Mar 26 17:00:00 mail amavis[1020]: Using primary internal av scanner
code for ClamAV-clamd
Mar 26 17:00:00 mail amavis[1020]: Found secondary av scanner
ClamAV-clamscan at /usr/bin/clamscan
Mar 26 17:00:00 mail amavis[1020]: Creating db in /var/lib/amavis/db/;
BerkeleyDB 0.42, libdb 4.8

I guess that I'm missing some packages but I don't know how to resolve
these issues in Debian. Does anyone know if there are packages which
specifically will satisfy the dependencies of Amavisd-new &
Clamav-daemon? If anyone knows what specifically I need in Debian to
satisfy these missing decoders, please let me know.

Thank you!