Windows 7 fails to install driver for Leonardo, unless HID is disabled

My leonardo works perfectly under ubuntu/linux 3.0.0-12. I wanted to test whether some stuff I built works with a windows pc. So I hooked up the leonardo to a pc running Windows 7 Home Premium SP1, 64bit. I had a lot of trouble (=understatement) installing a driver for the leonardo. It could install a driver for the booter mode, but not for the sketch mode.

If I watch device manager and plug in the leo, I see that a comm port is added. But as soon as the sketch starts running, the arduino is listed as an unknown device. I tried the "Update Driver" procedure as described in the "leonardo getting started guide": I pointed windows to the arduino-1.0.2/drivers directory. This operation fails: windows reports that a driver could not be found. (Btw, I also have the "RunOnce" registry key).

To rule out my sketch (or my core hacks) as a cause of trouble, I used the ide (on linux) to burn a bootloader to the leonardo. This also burns a fresh standard blink sketch.

Same result, windows cannot install the driver.

I decided to try without the HID (mouse,keyboard) stuff: in USBDesc.h I commented out this line:

//#define HID_ENABLED

, recompiled the sketch and uploaded it to the leonardo again using my linux box.
I verified in linux that now the sketch enumerates correctly as a device with only cdc/acm, no HID.

After that, windows installs the driver correctly, and serial port support works correctly too.

Can someone shed some light on this?
Did someone else observe this problem?
The .inf file for leonardo adds no driver for HID, isn't that a problem?

What is the VID/PID of the Leonardo in Device Manager when you had HID enabled?

Open Device Manager
Right Click the Device Manager \ Other Devices \ unknown device
Select Properties
Select Details tab
Choose Hardware Ids from the Property drop-down
What is the Hardware Ids that show in the Value section?

I verified it matched what was in the .inf file: 2341/8036.
To be sure I tried it again: uninstalled the windows driver; on linux reflashed the bootloader; connected to windows again.
I can't reproduce it anymore. This is crazy, I struggled a few evenings with this and now it is gone, I have no idea what manipulation solved it.

Sorry for the trouble and thanks anyway.