LinuxQuestions.org - kernel parameters for debian over nfs?

I'm playing around with some embedded systems, and I've gotten pretty far... however, I'm in a bit of a quandry. I've gotten my little device to boot over PXE and all, and I had it up and running on a small version of FreeBSD. However, I'd like to get Pebble linux on the box, but I'm having some trouble figuring out what the kernel parameter is for booting Debian (Pebble) from an nfs share.

(Before you ask, yes, I know the NFS share is working - I can boot my BSD image from it just fine, and I've changed all the DHCPD settings and pxeboot config settings to point to the right places).

On BSD, I use root=/dev/nfs - but there is no such thing on Pebble. Perhaps this distro is too stripped down for nfs? Or is there another parameter that I'm missing?

I'm not too used to Debian... although I'd like to get Pebble on this little device, I don't know that I'll be able to unless I boot another distro and copy the files over :-)