Guest Multiple processor and USB problems

[borgo1971]

In our office we have a MacMini Server with OS X 10.7 server, on which we run a Windows 2003 headless virtual machine. With the last Virtualbox upgrade (from 4.1.x to 4.2.1), I decided to give more resource to Windows 2003. After some days, we discovered that our management software for which we use Virtual Box, won't see his USB dongle (Eutron Smartkey 3).
After more than a day of tries, I've discovered that configuring more then one processor, causes guest operating system to not recognize the USB dongle. Enabling 2 processors for the guest, in Windows resource, the dongle is seen as unrecognized USB device, and can't find any driver for it. Going backward to one processor, Windows will automatically recognize the device as "Smartkey 3 USB". From Mac side, with "vboxmanage showvminfo", I can't see any difference between the VM's outside of the number of processors.
Can't understand the connection, but something makes it go wrong with 2 processors.

[blueytoo]

You have found bug #7462!