White screen on boot

I have a bit of a frustrating situation here. I've been testing out Solaris 10 x86 on a Shuttle (AMD proc) here to get a better understanding of Solaris and set up a little test bed for zfs/zpool stuff. And I'm liking it a lot... except that the other day, I rebooted the server and it gets past the GRUB prompt and then goes to a white screen and stops.
Nothing has changed on the hardware and I can boot the failsafe image just fine so it's not an obvious hardware issue. One thing - I removed the CD that I used for the initial install to add an internal disk. But that's been the situation for a little while.
I've run fsck on the main drive and everything appears OK. The boot drive is not full, and the boot doesn't appear to be getting very far into the process since I mounted the boot volume under /a in failsafe mode and did a touch reconfigure in the hopes that this would unblock it, but the file is still there after several reboots, so the reconfigure process isn't loading.
Any ideas ?

I'm afraid not. Without an installer disc there is nothing you can do except repair permissions with Disk Utility. But that isn't going to solve the problem, I'm afraid.

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