Its the way 2.6 and gentoo 2005.0 do it
I got the same thing, it's a Gentoo 2005.0 thing, I suspect a misconfiguration in the kernel (2.6).
After initial reboot, there is no /dev/sda or /dev/sda1 sda2 sda3 apparently it's /dev/discs/disc0/part1 or /dev/discs/disc0/part2 /dev/discs/disc0/part3
I personally don't like it. I've got too many years experience using /dev/sda or /dev/hda or whatever to go this longer route. This is why my fstab failed to initialize the system. If you edit your /etc/fstab.conf and change /dev/sda1 to /dev/discs/disc0/part1 and so on, it will work.
I can't figure out which option in the kernel gives me the older /dev/hda or /dev/sda stuff, I prefer backwards compatibility. I've enabled all the devfs stuff.