Comment 7 for bug 107023

In my case using gparted to resize a partition within the extended partition caused the problem.

dpkg -p gparted | grep Version
Version: 0.4.5-2

I suggest:

 fixed it up with booting from a live-cd and using a usb-key.
sfdisk -d /dev/hda>hda.out
where hda.out is in on my usb key.
then
sfdisk /dev/hda -O backup.hda<hda.out
to simply rewrite the partiton table saved as hda.out
the backup.hda is a backup (made on my usb key too) in case something goes
wrong.

or
b)
fdisk advanced mode
 by pressing x
show help m
and use the f option
write changes w

then reboot

you may also need to adjust your /boot/grub/menu.lst, and also your /etc/fstab

P.S.
I have included the gparted package version in the Description field
Also please refer to parted bug list.