This is after successful install right? From what I have found on the net it seems you need to reinstall boot blocks, something like this:
Code:
/usr/sbin/installboot /dev/rwd0a /usr/mdec/bootblk
Be cautious about this, it's something I found on the net, not from my personal experience.
Also, if you could, try installing newer 5.1 release and see if it gets better.
All best