if you read the previous posts you'll learn that this seems to be a "normal" thing. At least it was for me (on an IBM T43p) Just answer "not" and press control F3 (or was it F5?) to finish your installation. When you're done you'll probably have a fully functional debian-bsd system. Otherwise if you have a connection then just apt-get reinstall the kernel and wahtever you want.
Please, after rebooting into Debian GNU/kFreeBSD try "apt-get update; apt-get upgrade" (or even dist-upgrade). It will now bring to you FreeBSD 6.2 based kernel ;-) Petr