I run Windows 7 as a VM in VirtualBox on my MacBook Air (using OS X 10.7). If I do not shutdown the VM but save its machine state. The keyboard will behave strangely after resuming. It seems the Windows Logo key is always hold.

• When I type the key 'u', the Control Panel will be shown. I tested on a real Windows 7, the same dialog will be shown when I press Win-key and 'u'.
• When I type the key 'e', the Explorer will show up, some as press Win-key and 'e' on a real Windows 7.

If I click 'Restart' from the Start menu of Windows 7, after restarting the VM, the keyboard works again. I think there are some conflicts with keyboard driver in VM. It is quite annoying, usually I usually close a VM by saving its machine state, not shut the OS down. Is there any way to solve this problem?