Bug with Intel 6 Series/C200 Series Chipset Family USB Controller

I have the Microsoft Natural Ergonomic 7000 keyboard/mouse wireless USB.  I have two PCs running Windows 7 Ultimate x64, both using the Intel Z68 chipset (one motherboard is from Gigabyte and the other is from Asus).  This chipset appears to have the Intell 6 Series/C200 Series USB Controller.

The problem I have is when the computer is in sleep mode.  It wakes up on its own after a short period of time.  powercfg -lastwake shows that it's the USB controller.

I did some experimentation and went to the Power Management tab for the mouse under device manager.  The box "Allow this device to wake the computer" is checked.  I uncheck it and put the computer  back to sleep.  I move the mouse or click on a button and the computer wakes up when it's not supposed to.  I go back into device manager and this time, I uncheck "Allow this device to wake the computer" for the keyboard and check (enable) it for the mouse. 

I put the computer to sleep and click on a key. The computer wakes up when it should not. 

I then uncheck "Allow this device to wake the computer" for both the keyboard and mouse.  Again, I put the computer to sleep.  This time, clicking on the mouse or the keyboard does not cause the computer to wake up.

I tried the keyboard/mouse on an older computer (Core 2 Duo 2007) that is also running Windows 7 Ultimate.  This board has the Intel 82801G (ICH7 Family) USB Controller. With this board, the Microsoft 7000 keyboard/mouse wireless USB works perfectly.  That is:

1. It does not wake up on its own with no activity on the mouse or keyboard

2.  If the mouse is set to not be able to wake the computer, clicking on the mouse while the computer is asleep has no effect

3. If the keyboard is set to not be able to wake the computer, typing on the keyboard while the computer is asleep has no effect.

So I think there's a bug with the Z68 Chipset USB driver.  Do you agree?