How to find out apt-get's reasoning

[Jonathan Matthews <jaycee.removeifnotspam@jaycee.uklinux.net>]

Having just installed the Gnome 2.2 backport, I'm trying to drop kde 
from my box totally.  Never liked the "underline the desktop icons" 
thing anyway[1] :-)

I thought I'd got it all out, but witness the following:

bigdaddy:/home/jaycee# apt-get dist-upgrade -u
[snip]
The following NEW packages will be installed:
  kdelibs-data 
The following packages have been kept back
  gnu-smalltalk imagemagick libcurl2 liblcms1 liblcms1-dev libmng-dev 
libmng1 libpng12-0 libpng12-0-dev libpng3 libwmf0.2-7
  mpeglib tetrinetx 
0 packages upgraded, 1 newly installed, 0 to remove and 13  not 
upgraded.

I'm not asking anyone to tell me why my particular mix of sources is 
doing this, I'm wondering more if there's a grep-available or grep-dctrl 
invocation that might tell me which *installed* packages *depend* on 
kdelibs-data.  Yes, I know "kdelibs & kdelibs4", but neither of them is 
installed.

Any takers?

Cheers!
jc

--

[1] Joke. JOKE!