[~]# apt-cache policy libsasl2-2
libsasl2-2:
  Installed: 2.1.22.dfsg1-5
  Candidate: 2.1.22.dfsg1-8
  Version table:
     2.1.22.dfsg1-8 0
        500 http://ftp.debian.org etch/main Packages
 *** 2.1.22.dfsg1-5 0
        100 /var/lib/dpkg/status
[~]# apt-cache policy postfix   
postfix:
  Installed: 2.3.4-2
  Candidate: 2.3.7-3
  Version table:
     2.3.7-3 0
        500 http://ftp.debian.org etch/main Packages
 *** 2.3.4-2 0
        100 /var/lib/dpkg/status