On Ubutu Natty fully during update of grub-PC I got this error message.

Could someone explain what this is about:

Paramétrage de grub-pc (1.99~rc1-13ubuntu3) ...
/usr/sbin/grub-setup: warn: This GPT partition label has no BIOS Boot Partition; embedding won't be possible!.
/usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
Installation finished. No error reported.
Generating grub.cfg ...