This probably started happening to VBox after I let through a kernel update – usually I did “keep current menu.lst” when asked by Update Manager. The driver it complained about is the network, which caused it to be unable to attach to eth3 in bridged mode. The good thing is, after following the very helpful suggestion in the error message – run /etc/init.d/vboxdrv setup as root – it resolved itself in about a minute. That’s much easier to do than VMWare Server, which requires a complete reconfigure.
I don’t remember this happening to my VBox before though, when it’s still Sun Virtual Box and it was running on Jaunty. I always let kernel update to be applied then.