dedibox1:~# dpkg -s postfix
Package: postfix
Status: deinstall ok config-files
Priority: extra
Section: mail
Installed-Size: 2448
Maintainer: LaMont Jones <lamont@debian.org>
Architecture: i386
Version: 2.3.6-1
Config-Version: 2.3.6-1
Replaces: postfix-doc (<< 1.1.7-0), postfix-tls, mail-transport-agent
Provides: mail-transport-agent, postfix-tls
Depends: libc6 (>= 2.3.6-6), libdb4.3 (>= 4.3.28-1), libsasl2-2, libssl0.9.8 (>= 0.9.8c-1), debconf (>= 0.5) | debconf-2.0, netbase, adduser (>= 3.48), dpkg (>= 1.8.3), lsb-base (>= 3.0-6), ssl-cert
Recommends: mail-reader
Suggests: procmail, postfix-mysql, postfix-pgsql, postfix-ldap, postfix-pcre, sasl2-bin, libsasl2-modules, resolvconf, postfix-cdb
Conflicts: mail-transport-agent, smail, libnss-db (<< 2.2-3), postfix-tls
Conffiles:
 /etc/init.d/postfix 1de31367a667ffffba2470bb48f417f6
 /etc/ppp/ip-up.d/postfix fccc53fc4eeeab46941ebcc95a71e766
 /etc/ppp/ip-down.d/postfix 52275dc23864f3bfca412c7558e28fe6
 /etc/network/if-up.d/postfix fccc53fc4eeeab46941ebcc95a71e766
 /etc/network/if-down.d/postfix 52275dc23864f3bfca412c7558e28fe6
 /etc/postfix/postfix-script 1b9f1c7cfdb4a58dec3c658bac58199f
 /etc/postfix/post-install 1b19c37485242a67f06df1453cd64c57
 /etc/postfix/postfix-files 9ed1078e4321170e4d2d52fbd5d92f63
 /etc/resolvconf/update-libc.d/postfix 3c921a0c2447ae3e166a62411568d048
Description: A high-performance mail transport agent
 Postfix is Wietse Venema's mail transport agent that started life as an
 alternative to the widely-used Sendmail program.  Postfix attempts to
 be fast, easy to administer, and secure, while at the same time being
 sendmail compatible enough to not upset existing users. Thus, the outside
 has a sendmail-ish flavor, but the inside is completely different.
dedibox1:~#