apt-cache policy libc6 libc-i386
libc6:
  Installed: 2.3.6.ds1-13etch5
  Candidate: 2.3.6.ds1-13etch5
  Version table:
 *** 2.3.6.ds1-13etch5 0
        500 http://ftp.ntua.gr etch/main Packages
        100 /var/lib/dpkg/status
     2.3.6.ds1-13 0
        500 cdrom://[Debian GNU/Linux 4.0 r0 _Etch_ - Official amd64 DVD Binary-1 20070407-12:15] etch/main Packages
W: Unable to locate package libc-i386