Vista updates on notebook while in sleep mode?

Hi,
My Vista/SP2 notebook has had no problems.
Except for this:
I put it to sleep last nite, but this morning it was awake.
And, there was an auto update installed:
MSE client update package KB2254596

The same happened several weeks ago.
And as I remember that had an update as well.
I have auto update set to run at 3:00AM.
What happened here?

A. Notebook problem where it did not go to sleep properly.
This is possible, but I think I would have noticed the led on.

B. The auto update causes it to wake up at 3:00AM and check for updates
even when asleep? Is that possible?
I thought that only task schedular tasks could bring a PC out of sleep.
I see only one task that has "Wake the computer to run this task".
It is MobilePC/TMM, which seems unrelated.
I also seem to remember that some NIC cards can be set to wake up
a PC. I have never fiddled with that.

thanks
gordon

Yes, you nailed it. If your NIC card is set to wake the computer. It will wake you when updates are available. You can turn it off, if you like:
Device manager
Network adapters double click
Right Click
Properties
change settings
power managment
Untick the box wake

Rich,
Both my wireless network adapter and ethernet controller
did not have the "Allow this device to wake the computer" enabled.
I believe that is the default setting.
I will watch it more carefully.

thanks
gordon