howto find out why dist-upgrade wants to remove a package?

[Hugo Vanwoerkom <hvw59601@care2.com>]

Hi,

Running Sid, and I don't want apt to upgrade apache or php4.

So I pinned them in /etc/apt/preferences:

Explanation: Keep apache + php4 around for WP's lists...
Package: apache
Pin: version 1.3.34
Pin-Priority: 1001

Package: apache-common
Pin: version 1.3.34
Pin-Priority: 1001

Package: php4-common
Pin: version 4.4.4
Pin-Priority: 1001

Package: php4-mysql
Pin: version 4.4.4
Pin-Priority: 1001

Package: libapache-mod-php4
Pin: version 4.4.4
Pin-Priority: 1001

But it only partly works: when I do apt-get distupgrade I get:

...
The following packages will be REMOVED:
  fftw3 gpm libgsl0 libhd13 libldap2 librpm4 libstlport4.6c2 php4-mysql
...

So what I pinned to 1001 he wants to remove!

How do I find out why he wants to remove a package?

Thanks.

Hugo