I managed to compile a bootable kernel for my N800 following the steps in the OP using this commit from the linux-omap git:

eba014745cc806d625b6a553d1af6efd14e16321

If you check out the latest the patches wont apply...


EDIT:

To summarise, ignore Capn_Fish's post on the last page, as he seems to have tmr and the other guy confused...

Follow the instructions in the first post, but instead of checking out the latest from the linux omap git:

get the snapshot from the commit referenced above:

http://git.kernel.org/?p=linux/kerne...af6efd14e16321

Click on 'snapshot' on that page and extract. Use that in place of the linux-omap-2.6 folder in the instructions...