Comment 2 for bug 154490

It does in Gutsy Gibbon. I'm on Hardy Heron now, but I don't know whether it still happens, and since I have not backed up my data yet, I do not intend to try it out anytime soon...

Yes, it might also be a bug in Vista. But Vista operates correctly when it's own boot manager manges the boot sequence, so the bug only happens with GRUB, at least for me.