Applied SP4-now no standby

Sharp Actius MV-10W, worked fine under SP2, but
all the security issues prompted me to do SP4.

All's OK, but the machine won't go into standby as
specified in the Power options.

If I do it manually, from the Start button, it works OK,
so I know the functionality is there.

I have tried changing the time from one value to another
and Apply'ing it to see if it would "reset" things-no luck.

HD and display still power down automatically as usual.

Thx for any help.