I've made a patch to Eduardo de Barros Lima's port of Xournal (http://etrunko.blogspot.com/2006/07/xournal-package-for-it2006.html) so that it works on Nokia N800.

Here's the deb file: xournal_0.3.1-indt3N800fix_armel.deb 

The changelog:  xournal_0.3.1-indt3N800fix_armel.changes

Patched sources: xournal_0.3.1-indt3N800fix.tar.gz 

 Installation instructions:

First install application from original author's repository:

Repository: http://www.bgran.net/etrunko/apt
Distribution: mistral
Component: user

Then download and install deb file above.