Problem: kernel-image install -> menu.lst updated with wrong partition info

[<Hassenpflug.Ismail@mb3.seikyou.ne.jp>]

Hello list,

My first attempt at posting a qustion, thanks very much in advance.

* S/W: GNU/Linux Debian unstable
       Microsoft Windows XP Home Edition
* H/W: Inspiron 1100, hda is CD-ROM, hdc is HDD
* Bootloader: GRUB in MBR
* partition information:
  /dev/hdc1 : MS Windows XP
  /dev/hdc2 : /boot
  /dev/hdc3 : /
  /dev/hdc4 : Extended partition
  /dev/hdc5 : /share
  /dev/hdc6 : Linux Swap partition

History: 

Many attempts at installs and different partitioning schemes, migrating
from Debian testing to Debian unstable initially because of multimedia
applications (and didn't know about pinning!).

Problem:

When installing a new "linux-image-*" with "apt-get install", GRUB's
"/boot/grub/menu.lst" is updated automagically - but to incorrect information
regarding (hd0,X) and root=/dev/hdcY. This corresponds to some older information
but I have not been able to find the offending repository of this information. 
I have tried to reinstall grub, remove the /boot/grub directory, remove backup 
(*~) files, but to no avail. Each time I install a new kernel image, my menu.lst 
becomes incorrectly updated. I am sure this is a trivial issue, but I could not 
find any information on Google. I trust this will not make you all laugh too 
much at my limited abilities!

Many thanks in advance,
        Gernot Hassenpflug