After installing a ZFS only build, machine won't complete POST

[John Terrell]

Has anyone seen this?  I've just installed a ZFS only build following the instructions at (http://wiki.freebsd.org/RootOnZFS/GPTZFSBoot).   After rebooting after the install, the POST won't complete (it appears to be looking at the disks for something).   If I unplug the drives and reboot, POST completes.  If I then destroy the GPT partitions and install MBR, I can now get past POST (but with a corrupted installation that won't boot).  

Some info:
Motherboard: MSI Neo2
Disks:  2x 500GB Seagates (I created a mirrored pool during installation).

Could this just be a crappy BIOS issue?   I'd hate to have to scrap GPT/ZFS and go back to MBR/UFS.

Any ideas?

Thanks.

-John