hd sleep

[Matthieu Amiguet]

I like to work in silence, and I usually use a command like 
hdparm -S 12 /dev/hda
to spin down my disk when not in use.
I tried to do this on my YDL 2.0 system, but the disk keep spinning up as 
soon as it has stopped.
I tried to add  -s 3660 -f 3600 as options to /sbin/update in /etc/inittab, 
but the problem is the same.
I was using LinuxPPC before, and the spinning down of the disk worked, so it 
is not an hardware issue.
The problem remains in single mode (telinit 1), so it is not an editor saving 
regularly or an exotic daemon... any idea?

My system:

Imac 400mhz (slot-loading)
320MB RAM
YDL 2.0
kernel 2.2.19-1k
hdparm-3.9-6

Matthieu