Let's not make this fix about solving USB and Virtualbox, it's about Lucid not booting when "none /proc/bus/usb usbfs" is in fstab which could cause problems with upgrades.
Concerning Virtualbox, I had the same error message, but now it works, maybe the Lucid updates fixed it. No need for putting "none /proc/bus/usb usbfs" in fstab anymore.
Let's not make this fix about solving USB and Virtualbox, it's about Lucid not booting when "none /proc/bus/usb usbfs" is in fstab which could cause problems with upgrades.
Concerning Virtualbox, I had the same error message, but now it works, maybe the Lucid updates fixed it. No need for putting "none /proc/bus/usb usbfs" in fstab anymore.