Ah. Then I would agree that there are 2 rootvgs trying to live on your machine. Try "man alt_disk_installation" and get an idea of what it does. I'd back out...reinstall 4.3.3 on hdisk0 and set it...
Did you do an alt_disk_installation of 5.1? Did it go in clean? Still waiting on AIX 5, but have moved from 4.3.3.0 to 4.3.3.0.06 with alternate disk installation without issues. Is there any...