booting from label inside GPT partition / EFI loader for amd64?

Hello,

I'm trying to boot (load the loader) from ad4p2a. Should that be possible?
gptboot claims "no UFS filesystem found" and the ordinary bootcode just 
prints Boot Error.

I have an intel i386 server board which supports EFI booting, but I 
think I cannot use the ia64 efi loader, right?
Is there any development bits I can try making my server EFI booting?

Thanks,

-Harry