sarge + 2.6.12 kernel panic

[John O'Hagan <johnohagan@iprimus.com.au>]

Just installed sarge, got fresh kernel sources for 2.6.12, used an oldconfig 
from a previously successful 2.6.11 kernel, and compiled. Unfortunately when 
I tried to boot that kernel I got this:

	attempt to access beyond end of device
	hda2: rw=16, want=8, limit=2
	kernel panic - not syncing: I/O error reading memory image

I accepted the default sarge partitioning scheme for a desktop machine, so / 
is on hda1, and hda2 is an extended partition containing logical partitions 
hda5 and hda6 (I wonder why those numbers?).

I have found some references to this issue but they're a little over my head.

The default kernel boots fine, and there are few significant differences in 
the configs., that I can see anyway.

Does anyone know about this issue, or how to fix it? 

Please CC me.

Thanks,

John