qtparted and kernel disagree about partitions

[David Goodenough <david.goodenough@btconnect.com>]

I have a hard drive with a primary partition and an extended partiton.
QTParted says that it has /dev/hda1, /dev/hda2 and /dev/hda5 which is
what one would expect, but when I boot the disk the kernel reports
that there are only the /dev/hda1 and /dev/hda2 partitons, no /dev/hda5.

The really odd thing is that qtparted is running on the kernel which 
can not see /dev/hda5.

The disk is question is a 2.5" 160GB drive, and is quite new.  The kernel
log shows no errors.

Any idea what might cause this and how to fix it (preferably without
repartitioning the disk as backing it all up would take a while and also
I do not know how I would access the data in /dev/hda5 if I can not see
it).

David