Não é possível instalar o libpq-dev no debian wheezy

Question

Eu já tenho deb http://apt.postgresql.org/pub/repos/apt/ wheezy-pgdg main no meu arquivo /etc/apt/sources.list.

Eu tentei seguir a trilha da dependência, mas cheguei a um beco sem saída. É assim que acontece:

sudo apt-get install libpq-dev
(...)
The following packages have unmet dependencies:
 libpq-dev : Depends: krb5-multidev but it is not going to be installed

sudo apt-get install krb5-multidev
(...)
The following packages have unmet dependencies:
 krb5-multidev : Depends: libkrb5-3 (= 1.10.1+dfsg-5+deb7u3) but 1.13~alpha1+dfsg-1 is to be installed
                 Depends: libk5crypto3 (= 1.10.1+dfsg-5+deb7u3) but 1.13~alpha1+dfsg-1 is to be installed
                 Depends: libgssapi-krb5-2 (= 1.10.1+dfsg-5+deb7u3) but 1.13~alpha1+dfsg-1 is to be installed

sudo apt-get install libkrb5-3=1.10.1+dfsg-5+deb7u3
(...)
The following packages have unmet dependencies:
 libkrb5-3 : Depends: libkrb5support0 (= 1.10.1+dfsg-5+deb7u3) but 1.13~alpha1+dfsg-1 is to be installed

E é aí que está o problema. Se eu tentar instalar a versão libkrb5support0, ela precisa me avisar que cerca de 1,6 GB de software serão removidos, incluindo texlive, nautilus, libreoffice ou openssh, por exemplo. Alguma idéia?

Editar

cat /etc/debian_version
7.8

apt-cache show krb5-multidev

Package: krb5-multidev
Source: krb5
Version: 1.10.1+dfsg-5+deb7u3
Installed-Size: 687
Maintainer: Sam Hartman <[email protected]>
Architecture: amd64
Depends: libkrb5-3 (= 1.10.1+dfsg-5+deb7u3), libk5crypto3 (= 1.10.1+dfsg-5+deb7u3), libgssapi-krb5-2 (= 1.10.1+dfsg-5+deb7u3), libgssrpc4 (= 1.10.1+dfsg-5+deb7u3), libkadm5srv-mit8 (= 1.10.1+dfsg-5+deb7u3), libkadm5clnt-mit8 (= 1.10.1+dfsg-5+deb7u3), comerr-dev
Suggests: krb5-doc
Description-en: Development files for MIT Kerberos without Heimdal conflict
 Kerberos is a system for authenticating users and services on a network.
 Kerberos is a trusted third-party service.  That means that there is a
 third party (the Kerberos server) that is trusted by all the entities on
 the network (users and services, usually called "principals").
 .
 This is the MIT reference implementation of Kerberos V5.
 .
 Most users wishing to build applications against MIT Kerberos should
 install libkrb5-dev.  However, that package conflicts with heimdal-dev.
 This package installs libraries and headers in /usr/include/mit-krb5 and
 /usr/lib/mit-krb5 and can be installed along side heimdal-multidev, which
 provides the same facilities for Heimdal.
Homepage: http://web.mit.edu/kerberos/
Description-md5: 7761820aba399b20f00deab931782fe1
Section: libdevel
Priority: optional
Filename: pool/updates/main/k/krb5/krb5-multidev_1.10.1+dfsg-5+deb7u3_amd64.deb
Size: 153624
MD5sum: bf887d013aef226d69670372158df179
SHA1: 16f7601ac5e4b55b6860ebc0b72c0fe5102e11ed
SHA256: 79c1c6f379c36f31c0607e46f6bd19ea20a7c66ddaf8dd0474b0c264b74cc480

Package: krb5-multidev
Source: krb5
Version: 1.10.1+dfsg-5+deb7u2
Installed-Size: 687
Maintainer: Sam Hartman <[email protected]>
Architecture: amd64
Depends: libkrb5-3 (= 1.10.1+dfsg-5+deb7u2), libk5crypto3 (= 1.10.1+dfsg-5+deb7u2), libgssapi-krb5-2 (= 1.10.1+dfsg-5+deb7u2), libgssrpc4 (= 1.10.1+dfsg-5+deb7u2), libkadm5srv-mit8 (= 1.10.1+dfsg-5+deb7u2), libkadm5clnt-mit8 (= 1.10.1+dfsg-5+deb7u2), comerr-dev
Suggests: krb5-doc
Description-en: Development files for MIT Kerberos without Heimdal conflict
 Kerberos is a system for authenticating users and services on a network.
 Kerberos is a trusted third-party service.  That means that there is a
 third party (the Kerberos server) that is trusted by all the entities on
 the network (users and services, usually called "principals").
 .
 This is the MIT reference implementation of Kerberos V5.
 .
 Most users wishing to build applications against MIT Kerberos should
 install libkrb5-dev.  However, that package conflicts with heimdal-dev.
 This package installs libraries and headers in /usr/include/mit-krb5 and
 /usr/lib/mit-krb5 and can be installed along side heimdal-multidev, which
 provides the same facilities for Heimdal.
Homepage: http://web.mit.edu/kerberos/
Description-md5: 7761820aba399b20f00deab931782fe1
Tag: admin::login, admin::user-management, devel::lang:c, devel::library,
 implemented-in::c, network::client, protocol::kerberos,
 role::devel-lib, security::authentication, security::cryptography,
 use::login
Section: libdevel
Priority: optional
Filename: pool/main/k/krb5/krb5-multidev_1.10.1+dfsg-5+deb7u2_amd64.deb
Size: 153496
MD5sum: 98b229beff22debe70d1deb61f965f23
SHA1: 56c8c197fd2511ba7c72b20d66a78087351dc24d
SHA256: 354ec830b64b33f750ce21b10ec84238d62847a4601b5392cab0da95b76d8d5d

apt-cache policy krb5-multidev

krb5-multidev:
  Installed: (none)
  Candidate: 1.10.1+dfsg-5+deb7u3
  Version table:
     1.10.1+dfsg-5+deb7u3 0
        500 http://security.debian.org/ wheezy/updates/main amd64 Packages
     1.10.1+dfsg-5+deb7u2 0
        500 http://ftp.es.debian.org/debian/ wheezy/main amd64 Packages

apt-cache policy libkrb5-3

libkrb5-3:
  Installed: 1.13~alpha1+dfsg-1
  Candidate: 1.13~alpha1+dfsg-1
  Version table:
 *** 1.13~alpha1+dfsg-1 0
        100 /var/lib/dpkg/status
     1.10.1+dfsg-5+deb7u3 0
        500 http://security.debian.org/ wheezy/updates/main amd64 Packages
     1.10.1+dfsg-5+deb7u2 0
        500 http://ftp.es.debian.org/debian/ wheezy/main amd64 Packages